A method for manufacturing a thin film antenna

Abstract

The application discloses a preparation method of a thin film antenna, and comprises the following steps: selecting a high-frequency low-loss PET film as a thin film base material, and performing heat setting and surface pretreatment on the thin film base material; preparing a tin-silver-copper alloy conductive paste containing tin, silver, copper and a flux; providing a stainless steel wire mesh, and reserving a size compensation amount in a wire mesh pattern design stage according to the thermal shrinkage rates of the thin film base material and the conductive paste; forming an antenna conductive pattern on the surface of the thin film base material by a screen printing method in a controlled temperature and humidity environment; performing segmented curing treatment of pre-baking and main curing on the antenna conductive pattern, and performing pattern precision detection and electrical property detection on the cured conductive layer; by the above method, the complexity and manufacturing cost of traditional PCB multilayer printing process can be reduced, the consistency, size stability and high-frequency working reliability of the thin film antenna array unit are improved, and the method is suitable for batch manufacturing of satellite internet terminals and millimeter wave phased array antennas.

Description

Technical Field

[0001] This invention relates to the field of phased array antenna and thin film printing manufacturing technology, and in particular to a method for preparing a thin film antenna. Background Technology

[0002] With the development of satellite internet, millimeter-wave communication, and phased array antenna technology, terminal devices are placing higher demands on the thinness, cost reduction, and mass production capabilities of antenna arrays. Existing phased array antennas typically employ PCB printing to form antenna patches, feed networks, or multilayer conductive structures. For millimeter-wave band phased array antennas, the small size of the antenna array elements means that parameters such as linewidth, spacing, element center position, and interlayer alignment accuracy directly affect the resonant frequency, impedance matching, beam pointing accuracy, and sidelobe level.

[0003] Traditional PCB manufacturing methods typically involve complex processes such as multilayer lamination, etching, drilling, copper plating, and pattern transfer, resulting in long manufacturing cycles and high material and equipment costs. Especially in satellite internet phased array antenna terminal equipment, continuing to use traditional multilayer PCB processes to fabricate the top-layer patch structure for millimeter-wave bands would be detrimental to low-cost, high-volume, and mechanized production.

[0004] While existing technologies exist for forming conductive patterns on thin film surfaces using screen printing, simply printing conductive paste onto a thin film is insufficient for high-frequency phased array antennas to address issues such as dimensional consistency, thermal shrinkage compensation, conductive layer uniformity, millimeter-wave loss, element position offset, and batch reliability. Therefore, it is necessary to provide a thin-film antenna fabrication method suitable for high-frequency phased array antennas. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for fabricating a thin-film antenna, so as to solve the problems of complex process, high cost, and difficulty in mass production when using PCB printing or multilayer fabrication process for existing phased array antennas, as well as the problems of pattern offset, poor array element consistency, uneven conductive layer thickness and increased high-frequency loss in the millimeter wave band.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for fabricating a thin-film antenna, comprising the following steps: S1. Select a thin film substrate and perform heat setting treatment on the thin film substrate; S2. Perform surface pretreatment on the heat-set film substrate to remove oil, dust and impurities from the surface of the film substrate; S3. Prepare a tin-silver-copper alloy conductive paste, which is used to form the conductive pattern of the thin-film antenna; S4. Provide a stainless steel wire mesh, and form an antenna pattern opening on the stainless steel wire mesh that corresponds to the thin-film antenna to be prepared; S5. Based on the thermal shrinkage rate of the thin film substrate and the tin-silver-copper alloy conductive paste, reserve a size compensation amount in the design size of the antenna pattern opening; S6. The stainless steel wire mesh is positioned opposite to the thin film substrate, and the tin-silver-copper alloy conductive paste is transferred to the surface of the thin film substrate by screen printing to form an antenna conductive pattern. S7. Perform pre-baking and main curing segmented curing treatment on the thin film substrate on which the antenna conductive pattern is formed to form a conductive layer. S8. Perform pattern accuracy and electrical performance testing on the cured conductive layer to obtain the thin-film antenna.

[0007] The beneficial effects of this invention are as follows: The method for preparing a thin-film antenna provided by this invention achieves dimensional stability by selecting a thin-film substrate and performing heat setting treatment, thus avoiding the displacement of antenna element spacing caused by substrate expansion and contraction under high and low temperature environments; by performing surface pretreatment on the heat-set thin-film substrate to remove oil, dust, and impurities, the conductive paste achieves good adhesion, preventing subsequent peeling and flaking; by formulating a tin-silver-copper alloy conductive paste to form an antenna conductive pattern, the thin-film antenna obtains a conductive layer suitable for high-frequency phased array antennas; by providing a stainless steel mesh and forming antenna pattern openings on the stainless steel mesh, the screen printing achieves precise pattern transfer capability; by reserving a dimensional compensation amount in the design size of the antenna pattern openings according to the thermal shrinkage rate of the thin-film substrate and the tin-silver-copper alloy conductive paste, the cured... The antenna conductive pattern achieves actual dimensions consistent with the design size, offsetting dimensional errors caused by thermal shrinkage. The antenna conductive pattern is formed by screen printing a tin-silver-copper alloy conductive paste onto the surface of the thin-film substrate using a stainless steel mesh positioned opposite the substrate. This enables low-cost, high-volume, and mechanized production of thin-film antennas. A segmented curing process, including pre-baking and main curing, is applied to the thin-film substrate with the antenna conductive pattern to form a conductive layer. This ensures complete curing, preventing low conductivity due to excessively low curing temperature or thermal shrinkage and warping due to excessively high curing temperature. The cured conductive layer undergoes pattern accuracy and electrical performance testing to obtain the thin-film antenna, ensuring it meets the performance requirements of high-frequency phased array antennas in terms of array consistency, resonant frequency accuracy, and electrical reliability. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the thin-film antenna composition according to Embodiment 1 of the present invention; Figure 2 This is the transmission loss curve of Embodiment 1 of the present invention; Figure 3This is a schematic diagram of the wire mesh structure according to Embodiment 1 of the present invention.

[0009] Label Explanation: 1. Thin film substrate; 2. Antenna conductivity pattern; 3. Stainless steel wire mesh; 4. Antenna pattern opening. Detailed Implementation

[0010] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0011] Please refer to Figures 1 to 3 A method for fabricating a thin-film antenna includes the following steps: S1. Select a thin film substrate 1 and perform heat setting treatment on the thin film substrate 1; S2. Perform surface pretreatment on the heat-set film substrate 1 to remove oil, dust and impurities from the surface of the film substrate 1. S3. Prepare a tin-silver-copper alloy conductive paste, which is used to form the conductive pattern of the thin-film antenna; S4. Provide a stainless steel wire mesh 3, and form an antenna pattern opening 4 on the stainless steel wire mesh 3 that corresponds to the thin film antenna to be prepared; S5. Based on the thermal shrinkage rate of the thin film substrate 1 and the tin-silver-copper alloy conductive paste, reserve a size compensation amount in the design size of the antenna pattern opening 4. S6. The stainless steel wire mesh 3 is positioned opposite to the thin film substrate 1, and the tin-silver-copper alloy conductive paste is transferred to the surface of the thin film substrate 1 by screen printing to form the antenna conductive pattern 2. S7. Perform pre-baking and main curing segmented curing treatment on the thin film substrate 1 on which the antenna conductive pattern 2 is formed to form a conductive layer; S8. Perform pattern accuracy and electrical performance testing on the cured conductive layer to obtain the thin-film antenna.

[0012] As can be seen from the above description, the beneficial effects of the present invention are as follows: by selecting the thin film substrate 1 and performing heat setting treatment, the thin film substrate 1 obtains dimensional stability, avoiding the displacement of antenna element spacing caused by substrate expansion and contraction under high and low temperature environments; by performing surface pretreatment on the heat-set thin film substrate 1 to remove oil, dust and impurities, the conductive paste obtains good adhesion, avoiding subsequent peeling; by formulating a tin-silver-copper alloy conductive paste to form the antenna conductive pattern 2, the thin film antenna obtains a conductive layer suitable for high-frequency phased array antennas; by providing a stainless steel mesh 3 and forming antenna pattern openings 4 on the stainless steel mesh 3, the screen printing obtains precise pattern transfer capability; by reserving a size compensation amount in the design size of the antenna pattern opening 4 according to the thermal shrinkage rate of the thin film substrate 1 and the tin-silver-copper alloy conductive paste, the cured antenna conductive... The electrical pattern 2 achieves actual dimensions consistent with the design dimensions, offsetting dimensional errors caused by thermal shrinkage. The antenna conductive pattern 2 is formed by screen printing a tin-silver-copper alloy conductive paste onto the surface of the thin film substrate 1, using a stainless steel wire mesh 3 positioned opposite to the thin film substrate 1. This enables low-cost, high-volume, and mechanized production of the thin film antenna. A conductive layer is formed by pre-baking and main curing the thin film substrate 1 with the antenna conductive pattern 2, ensuring complete curing and preventing low conductivity due to excessively low curing temperature or thermal shrinkage and warping due to excessively high curing temperature. The cured conductive layer undergoes pattern accuracy and electrical performance testing to obtain the thin film antenna, ensuring it meets the performance requirements of high-frequency phased array antennas in terms of array consistency, resonant frequency accuracy, and electrical reliability.

[0013] Furthermore, the film substrate 1 is a polyethylene terephthalate film with a thickness of 0.1 mm ± 0.02 mm.

[0014] As described above, by limiting the thin film substrate 1 to a polyethylene terephthalate film with a thickness of 0.1 mm ± 0.02 mm, the thin film antenna achieves lightweight and thin characteristics and provides a dielectric performance basis suitable for high-frequency phased array antennas. At the same time, the thickness of the thin film substrate 1 is precisely controlled to ensure the stability of the antenna resonant frequency.

[0015] Furthermore, the polyethylene terephthalate film is a high-frequency, low-loss shaped PET substrate with a dielectric constant Dk fluctuation range of no more than ±0.02, a dielectric loss Df of no more than 0.01@10GHz, and a surface roughness Ra of no more than 0.1μm.

[0016] As described above, by limiting the polyethylene terephthalate film to a high-frequency, low-loss shaped PET substrate with a dielectric constant Dk fluctuation range of no more than ±0.02, the antenna resonant frequency shift is effectively suppressed, ensuring the phase consistency of the entire array; by limiting the dielectric loss Df to no more than 0.01@10GHz, the high-frequency loss of the antenna is effectively controlled, and the radiation gain is improved; by limiting the surface roughness Ra to no more than 0.1μm, the high-frequency conductor loss is reduced, ensuring the performance of the millimeter-wave band antenna. Furthermore, the tin-silver-copper alloy conductive paste comprises, by mass percentage: 94.5% tin, 3% silver, 0.5% copper, and 2% flux.

[0017] As described above, by limiting the tin-silver-copper alloy conductive paste to 94.5% tin, 3% silver, 0.5% copper, and 2% flux by mass percentage, the conductive paste achieves optimized solid content, viscosity, and thixotropy, ensuring printing consistency and providing the cured conductive layer with stable conductivity and oxidation resistance.

[0018] Furthermore, the particle size of the metal powder in the tin-silver-copper alloy conductive paste is no greater than 1 / 5 of the mesh size of the stainless steel wire mesh 3.

[0019] As described above, by limiting the particle size of the metal powder in the tin-silver-copper alloy conductive paste to no more than 1 / 5 of the mesh size of the stainless steel wire mesh 3, the metal powder achieves a match with the mesh count of the wire mesh, avoiding the problem of excessively large particle size clogging the mesh and causing missing prints or broken lines. At the same time, it avoids the problem of excessively small particle size causing powder agglomeration and reducing conductivity uniformity, thereby ensuring the integrity of the printed pattern and the uniformity of the conductive layer.

[0020] Furthermore, the stainless steel wire mesh 3 is a 301 stainless steel sheet with a thickness of 0.1mm ± 0.02mm. The tension of the stainless steel wire mesh 3 before printing is controlled between 25N / cm and 35N / cm, and the mesh accuracy deviation of the antenna pattern opening 4 is controlled within ±5μm.

[0021] As described above, by limiting the stainless steel wire mesh 3 to 301 stainless steel sheet with a thickness of 0.1mm ± 0.02mm, the wire mesh obtains sufficient mechanical strength and wear resistance; by limiting the tension of the stainless steel wire mesh 3 to 25N / cm to 35N / cm before printing, the stretching deformation of the printed pattern, the deviation of the array element spacing, and the uneven distribution of squeegee pressure are effectively controlled, thereby ensuring the consistency of the conductive layer thickness; by limiting the mesh accuracy deviation of the antenna pattern opening 4 to within ±5μm, the over-standard size of the antenna patch and the resonant frequency shift are suppressed, ensuring stable printing accuracy.

[0022] Furthermore, in step S2, the surface pretreatment includes alcohol wiping and / or plasma cleaning; in step S6, the screen printing environment temperature is controlled at 20°C to 25°C, with temperature fluctuations not exceeding ±2°C, and the environment humidity is controlled at 40%RH to 60%RH.

[0023] As described above, by limiting the surface pretreatment to alcohol wiping and / or plasma cleaning, oil, dust, and impurities on the surface of the thin film substrate 1 are thoroughly removed, and the adhesion of the conductive paste is improved. By limiting the screen printing environment temperature to 20℃ to 25℃ with temperature fluctuations not exceeding ±2℃ and the environmental humidity to 40%RH to 60%RH, the viscosity and flowability of the paste are stably controlled, avoiding inconsistent batch printing effects caused by temperature and humidity fluctuations, thereby ensuring the uniformity of the antenna array.

[0024] Furthermore, in step S6, the printing gap between the stainless steel wire mesh 3 and the thin film substrate 1 is controlled between 0.5 mm and 2 mm, and the squeegee pressure is kept uniform and the squeegee running speed is kept stable, so that the line width and spacing tolerance of the printed antenna conductive pattern 2 are controlled within ±10 μm, and the center position deviation of the array unit is not greater than ±5 μm.

[0025] As described above, by limiting the printing gap between the stainless steel wire mesh 3 and the thin film substrate 1 to 0.5mm to 2mm, pattern stretching deformation, dimensional deviation, and adhesion between the screen and the substrate are avoided; by maintaining uniform squeegee pressure and stable squeegee running speed, the resistance difference of each array element conductive layer is suppressed, avoiding array phase inconsistency and beam distortion; by controlling the line width and spacing tolerance of the printed antenna conductive pattern 2 within ±10μm, the unit resonant frequency deviation and array element coupling inconsistency are suppressed, avoiding array pattern distortion and gain attenuation; by limiting the center position deviation of the array unit to no more than ±5μm, the increase in beam pointing error, the rise in sidelobe level, and the decrease in grating lobe suppression capability are effectively controlled.

[0026] Furthermore, in step S7, the segmented curing process is carried out in a nitrogen inert atmosphere; the size compensation amount is 1% to 3% to compensate for the thermal shrinkage size error of the thin film substrate 1 and the tin-silver-copper alloy conductive paste during the curing process.

[0027] As described above, by limiting the segmented curing process to be carried out in a nitrogen inert atmosphere, the oxidation and blackening of the copper and tin alloy metal layer is effectively prevented, the stability of conductivity is guaranteed, and the increase in high-frequency loss is avoided. By limiting the size compensation amount to 1% to 3%, the thermal shrinkage size error of the thin film substrate 1 and the tin-silver-copper alloy conductive paste during the curing process is accurately offset, and the antenna pattern offset and the array element spacing disorder are avoided.

[0028] Furthermore, the thickness deviation of the cured conductive layer is controlled within ±10%; the pattern accuracy detection includes AOI optical inspection, and the electrical performance detection includes conductive layer sheet resistance detection and antenna element VSWR detection; and the thin film antenna is subjected to high and low temperature cycling test, damp heat aging test and / or bending reliability test.

[0029] As described above, by limiting the thickness deviation of the cured conductive layer to within ±10%, inconsistencies in the resistance and feed power of each channel are suppressed, and the decrease in array synthesis gain and excessive sidelobes are avoided. By limiting pattern accuracy testing, including AOI optical inspection, defects such as broken lines, short circuits, burrs, overflow, bubbles, and pattern deformation are comprehensively investigated, and defective products are prevented from flowing into the next process. By limiting electrical performance testing, including conductive layer sheet resistance testing and antenna element VSWR testing, the consistency of batch electrical performance is ensured. By conducting high and low temperature cycling tests, damp heat aging tests, and / or bending reliability tests on the thin-film antenna, long-term reliability issues such as conductive layer cracking, peeling, deformation, oxidation corrosion, and metal layer fracture failure are verified and eliminated.

[0030] Please refer to Figures 1 to 3 Embodiment 1 of the present invention is a method for fabricating a thin-film antenna, used to fabricate a thin-film patch layer for a phased array antenna. The thin-film antenna includes a thin-film substrate 1 and an antenna conductive pattern 2 formed on the surface of the thin-film substrate 1. The antenna conductive pattern 2 includes multiple antenna array elements arranged in an array. Depending on actual design requirements, the antenna conductive pattern 2 may also include a feed network, coupling structure, or connecting pads.

[0031] First, a PET film with a thickness of 0.1 mm ± 0.02 mm is selected as the film substrate 1. The PET film is made of high-frequency, low-loss shaped PET material, with a dielectric constant Dk fluctuation of no more than ± 0.02, a dielectric loss Df of no more than 0.01 @ 10 GHz, and a surface roughness Ra of no more than 0.1 μm. By controlling the above parameters, the impact of dielectric loss and size variation on antenna performance in the millimeter-wave band can be reduced.

[0032] Subsequently, the PET film undergoes heat setting to ensure its thermal expansion characteristics match those of the subsequently formed conductive metal layer, thereby reducing the element spacing shift caused by the expansion and contraction of the PET film under high and low temperature environments. After heat setting, the PET film is wiped with alcohol and cleaned with plasma to remove surface oil, dust, and impurities, improving the adhesion between the conductive paste and the PET film.

[0033] Next, a tin-silver-copper alloy conductive paste is prepared. The tin-silver-copper alloy conductive paste comprises 94.5% tin, 3% silver, 0.5% copper, and 2% flux by weight percentage. During the preparation process, the solid content, viscosity, and thixotropy of the paste are controlled to ensure stable transfer to the PET film surface through the stainless steel wire mesh 3. Preferably, the particle size of the metal powder in the conductive paste is no larger than 1 / 5 of the mesh size of the stainless steel wire mesh 3 to avoid clogging, printing defects, or line breaks due to excessively large particles.

[0034] Then, 301 stainless steel sheet is used as the wire mesh material, and the thickness of the stainless steel wire mesh 3 is 0.1mm ± 0.02mm. Before plate making, the stainless steel wire mesh 3 is cleaned and tension calibrated to control the wire mesh tension between 25N / cm and 35N / cm, and the mesh accuracy deviation of the antenna pattern opening 4 is controlled within ±5μm. According to the thin-film antenna design pattern, the corresponding antenna pattern opening 4 is formed on the stainless steel wire mesh 3.

[0035] When forming the antenna pattern opening 4, the thermal shrinkage rate of the PET film and the tin-silver-copper alloy conductive paste during the curing process is first tested, and a 1% to 3% dimensional compensation is reserved in the screen design stage based on the test results. This compensation is used to offset the thermal shrinkage during the pre-baking and main curing processes, so that the final cured antenna conductive pattern 2 matches the design dimensions.

[0036] Subsequently, screen printing was performed in an environment with a temperature of 20°C to 25°C and a humidity of 40%RH to 60%RH. During the printing process, the printing gap between the stainless steel screen 3 and the PET film was controlled between 0.5mm and 2mm, and the squeegee pressure was kept uniform and the squeegee running speed was kept stable. By comprehensively controlling the printing gap, squeegee pressure, and squeegee speed, the dimensional consistency of each antenna array unit was improved.

[0037] After printing, the antenna conductive pattern 2 on the PET film surface is pre-baked to remove some volatile components and initially stabilize the conductive pattern; subsequently, a main curing process is performed to solidify the tin-silver-copper alloy conductive paste into a stable conductive layer. Preferably, both pre-baking and main curing are carried out in a nitrogen inert atmosphere to reduce the risk of oxidation of the tin and copper components. After curing, flux residue on the surface and surrounding area of ​​the conductive layer is removed to avoid residues causing subsequent blistering, delamination, corrosion, or increased high-frequency dielectric loss during bonding.

[0038] The thickness deviation of the cured conductive layer is controlled within ±10%, the linewidth and spacing tolerance of the antenna conductive pattern 2 are controlled within ±10μm, and the center position deviation of the array element is no greater than ±5μm. For millimeter-wave band thin-film antennas, the surface roughness of the conductive layer is also controlled to Ra≤0.5μm, and it is ensured that there are no burrs or overflow at the edges of the conductive pattern to reduce parasitic capacitance, parasitic inductance, and high-frequency parameter offset.

[0039] When a composite antenna structure is required, the prepared thin-film antenna layer can be vacuum-bonded to a dielectric substrate and / or ground plane. During the bonding process, uniform pressure should be maintained, and interfacial air bubbles should be eliminated to avoid performance degradation of the antenna elements caused by localized air bubbles altering the dielectric constant distribution.

[0040] Finally, the fabricated thin-film antennas underwent AOI optical inspection to detect open circuits, short circuits, burrs, slurry overflow, bubbles, pattern deformation, dimensional deviations, and positional deviations. Simultaneously, the sheet resistance of the conductive layer and the standing wave ratio of the antenna elements were sampled and tested to confirm batch-to-batch electrical performance consistency. For flexible thin-film antennas, high and low temperature cycling tests, damp heat aging tests, and bending reliability tests were also conducted to verify that the conductive layer showed no cracking, peeling, deformation, oxidation corrosion, or significant performance degradation.

[0041] In summary, the method for fabricating thin-film antennas provided by this invention is suitable for mass production and mechanized manufacturing of phased array antenna terminal equipment for satellite internet.

[0042] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for fabricating a thin-film antenna, characterized in that, Includes the following steps: S1. Select a thin film substrate and perform heat setting treatment on the thin film substrate; S2. Perform surface pretreatment on the heat-set film substrate to remove oil, dust and impurities from the surface of the film substrate; S3. Prepare a tin-silver-copper alloy conductive paste, which is used to form the conductive pattern of the thin-film antenna; S4. Provide a stainless steel wire mesh, and form an antenna pattern opening on the stainless steel wire mesh that corresponds to the thin-film antenna to be prepared; S5. Based on the thermal shrinkage rate of the thin film substrate and the tin-silver-copper alloy conductive paste, reserve a size compensation amount in the design size of the antenna pattern opening; S6. The stainless steel wire mesh is positioned opposite to the thin film substrate, and the tin-silver-copper alloy conductive paste is transferred to the surface of the thin film substrate by screen printing to form an antenna conductive pattern. S7. Perform pre-baking and main curing segmented curing treatment on the thin film substrate on which the antenna conductive pattern is formed to form a conductive layer. S8. Perform pattern accuracy and electrical performance testing on the cured conductive layer to obtain the thin-film antenna.

2. The method for fabricating a thin-film antenna according to claim 1, characterized in that, The film substrate is a polyethylene terephthalate film with a thickness of 0.1 mm ± 0.02 mm.

3. The method for fabricating a thin-film antenna according to claim 2, characterized in that, The polyethylene terephthalate film is a high-frequency, low-loss shaped PET substrate with a dielectric constant Dk fluctuation range of no more than ±0.02, a dielectric loss Df of no more than 0.01@10GHz, and a surface roughness Ra of no more than 0.1μm.

4. The method for fabricating a thin-film antenna according to claim 1, characterized in that, The tin-silver-copper alloy conductive paste comprises, by weight percentage: 94.5% tin, 3% silver, 0.5% copper, and 2% flux.

5. The method for fabricating a thin-film antenna according to claim 4, characterized in that, The particle size of the metal powder in the tin-silver-copper alloy conductive paste is no greater than 1 / 5 of the mesh size of the stainless steel wire mesh.

6. The method for fabricating a thin-film antenna according to claim 1, characterized in that, The stainless steel wire mesh is made of 301 stainless steel sheet with a thickness of 0.1mm ± 0.02mm. The tension of the stainless steel wire mesh before printing is controlled between 25N / cm and 35N / cm, and the mesh accuracy deviation of the antenna pattern opening is controlled within ±5μm.

7. The method for fabricating a thin-film antenna according to claim 1, characterized in that, In step S2, the surface pretreatment includes alcohol wiping and / or plasma cleaning; in step S6, the screen printing environment temperature is controlled at 20°C to 25°C, with temperature fluctuations not exceeding ±2°C, and the environment humidity is controlled at 40%RH to 60%RH.

8. The method for fabricating a thin-film antenna according to claim 1, characterized in that, In step S6, the printing gap between the stainless steel wire mesh and the thin film substrate is controlled between 0.5 mm and 2 mm, and the squeegee pressure is kept uniform and the squeegee running speed is kept stable, so that the line width and spacing tolerance of the printed antenna conductive pattern is controlled within ±10 μm, and the center position deviation of the array unit is not greater than ±5 μm.

9. The method for fabricating a thin-film antenna according to claim 1, characterized in that, In step S7, the segmented curing process is carried out in a nitrogen inert atmosphere; the size compensation amount is 1% to 3% to compensate for the thermal shrinkage size error of the film substrate and the tin-silver-copper alloy conductive paste during the curing process.

10. The method for fabricating a thin-film antenna according to any one of claims 1 to 9, characterized in that, The thickness deviation of the cured conductive layer is controlled within ±10%; the pattern accuracy detection includes AOI optical inspection, and the electrical performance detection includes conductive layer sheet resistance detection and antenna element VSWR detection; furthermore, the thin film antenna is subjected to high and low temperature cycling test, damp heat aging test and / or bending reliability test.

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