A manufacturing method of a PDS antenna and electronic equipment

Abstract

The present application discloses a method for manufacturing a PDS antenna and an electronic device. The manufacturing method includes: groove manufacturing: manufacturing a groove on the stainless steel surface, wherein the groove extends to the junction of the stainless steel surface and the plastic surface; film layer manufacturing: forming a composite film layer including a nickel layer and a silver layer, or a composite film layer including a nickel layer and a gold layer, in the area of ​​the stainless steel surface located in the groove, and the surface of the composite film layer is lower than the plastic surface; tinning: manufacturing a tin soldering layer on the surface of the composite film layer, and the tin soldering layer is substantially flush with the plastic surface; silver paste printing: printing a silver paste pattern on the surface of the tin soldering layer and the plastic surface, and curing to obtain the PDS antenna. The PDS antenna manufactured in the present application has better bonding strength with the composite film layer through the tin soldering layer, thereby indirectly improving the bonding strength between the PDS antenna and the stainless steel surface.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a method for manufacturing a PDS antenna and an electronic device. Background Art

[0002] In the field of electronic equipment manufacturing, antennas are important signal receiving and transmitting components, and their performance is crucial to the communication quality of the equipment.

[0003] As electronic devices evolve towards miniaturization and higher performance, stainless steel and plastic injection molding are increasingly used. Compared to pure plastic housings, these materials offer superior high-temperature resistance and dimensional stability. However, when applying silver paste directly to stainless steel surfaces using the Printing Direct Structure (PDS) process, poor adhesion between the silver paste and the stainless steel can occur. Therefore, a new method for fabricating PDS antennas is urgently needed. Summary of the Invention

[0004] In response to the above technical problems, the present application provides a method for manufacturing a PDS antenna and an electronic device, which can improve the problem of poor adhesion strength between the silver paste and stainless steel of the PDS antenna manufactured by the existing method.

[0005] To solve the above technical problems, in a first aspect, an embodiment of the present application provides a method for manufacturing a PDS antenna, wherein the carrier of the PDS antenna includes a stainless steel surface and a plastic surface, and the manufacturing method includes:

[0006] Groove making: making a groove on the stainless steel surface, wherein the groove extends to the junction of the stainless steel surface and the plastic surface;

[0007] Film layer production: forming a composite film layer including a nickel layer and a silver layer, or a composite film layer including a nickel layer and a gold layer, on the surface of the stainless steel in the area located in the groove, wherein the surface of the composite film layer is lower than the plastic surface;

[0008] Tinning: forming a tin soldering layer on the surface of the composite film layer, and the tin soldering layer is substantially flush with the plastic surface;

[0009] Silver paste printing: printing a silver paste pattern on the surface of the tin soldering layer and the plastic surface, and curing the silver paste to obtain the PDS antenna.

[0010] Optionally, the steps of manufacturing the film layer include:

[0011] Provide stainless steel sheets;

[0012] forming the composite film layer on the surface of the stainless steel sheet;

[0013] The side of the stainless steel sheet facing away from the composite film layer is welded to the groove.

[0014] Optionally, the tinning step includes:

[0015] coating a tin layer on the surface of the composite film layer;

[0016] At 145~185℃, pressure 5~10N / mm 2 The tin layer is hot-pressed under conditions of to obtain the tin soldering layer.

[0017] Optionally, in the silver paste printing step, PDS silver paste of the first viscosity is used;

[0018] The tinning step further includes:

[0019] Filling ink: PDS silver paste with a second viscosity is provided at the interface between the tin soldering layer and the plastic, wherein the second viscosity is less than the first viscosity.

[0020] Optionally, the first viscosity is 4-6 Pa·s, and the second viscosity is 2-3 Pa·s.

[0021] Optionally, the composite film layer further includes: a chromium layer formed on the surface of the groove.

[0022] Optionally, the thickness of the chromium layer is 0.1-0.3 μm; and / or,

[0023] The thickness of the nickel layer is 2-4 μm; and / or,

[0024] The thickness of the silver layer is 1-3 μm; and / or,

[0025] The thickness of the gold layer may be 0.2-0.5 μm.

[0026] Optionally, the plastic is polyphenylene sulfide;

[0027] Before the tinning step, the method further comprises:

[0028] Surface etching: performing laser etching on the plastic surface to make the roughness of the plastic surface Ra0.5~1.2μm.

[0029] Optionally, the laser has a wavelength of 355 nm, a power of 5 to 15 W, a frequency of 20 to 50 kHz, and a scanning speed of 50 to 200 mm / s.

[0030] In a second aspect, the present application also provides an electronic device, including a shell and a PDS antenna, wherein the inner surface of the shell includes a stainless steel surface and a plastic surface, and the PDS antenna is formed on the stainless steel surface and the plastic surface, and is formed using the manufacturing method described in the above embodiments.

[0031] As described above, the PDS antenna fabrication method of the present application forms a composite film layer on a stainless steel surface. The nickel layer provides excellent bonding strength to the stainless steel and provides a more active surface for the silver or gold layer. The silver or gold layer provides a base for the tin solder layer, improving solder adhesion. Finally, a silver paste pattern (i.e., the PDS antenna pattern) is printed and cured to complete the PDS antenna fabrication. The tin solder layer and the composite film layer provide enhanced bonding strength, indirectly improving the bonding strength between the PDS antenna and the stainless steel surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without inventive work.

[0033] Figure 1 1 is a flow chart of a method for manufacturing a PDS antenna provided in an embodiment of the present application;

[0034] Figure 2 is a partial cross-sectional schematic diagram of a housing provided in an embodiment of the present application;

[0035] Figure 3 Schematic diagram after making grooves for the shell;

[0036] Figure 4 Schematic diagram of the shell after the composite film layer is made;

[0037] Figure 5 Schematic diagram of the shell after the tin soldering layer is made;

[0038] Figure 6 This is a schematic diagram of the shell after printing the silver paste pattern;

[0039] Figure 7 is a partial cross-sectional schematic diagram of another housing after forming a PDS antenna provided by an embodiment of the present application;

[0040] Figure 8 Schematic diagram of the morphology of the PPS surface before and after etching in the embodiment of the present application, where (a) is the morphology before etching and (b) is the morphology after etching.

[0041] The purpose of this application, its features, and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings. The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and the accompanying text are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of this application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0042] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0043] As mentioned above, when manufacturing a PDS antenna on a stainless steel or plastic injection molded housing, there is a problem of poor adhesion strength between the silver paste and the stainless steel. Based on this, the present application provides a method for manufacturing a PDS antenna and an electronic device.

[0044] See also Figure 1 , Figure 1 : is a flow chart of a method for manufacturing a PDS antenna provided in an embodiment of the present application. The carrier of the PDS antenna includes a stainless steel surface 10 and a plastic surface 20. The manufacturing method may include:

[0045] S101, groove making: making a groove on the stainless steel surface, wherein the groove extends to the junction of the stainless steel surface and the plastic surface.

[0046] The carrier, or housing, of the PDS antenna in this embodiment is injection-molded from stainless steel and plastic. For example, the stainless steel can be 316L stainless steel, which offers excellent corrosion resistance and mechanical properties. The plastic can be a composite of one or more polymers, such as PP (polypropylene), ABS (acrylonitrile butadiene styrene), PC (polycarbonate), or TPU (thermoplastic polyurethane). PPS (polyphenylene sulfide) is preferred, and glass fiber can be added, for example, with a glass fiber content of 40%. PPS is a thermoplastic engineering plastic with excellent mechanical strength, high-temperature and chemical resistance, and good thermal stability. The injection-molded 316L stainless steel and PPS form a housing that is dimensionally stable, resistant to high temperatures, and corrosion-resistant.

[0047] See also Figure 2 and Figure 3 , Figure 2 is a partial cross-sectional schematic diagram of a housing provided in an embodiment of the present application, Figure 3 This is a schematic diagram of the housing after the groove is formed. Before forming groove 11, the stainless steel surface can be cleaned, for example, using plasma cleaning to remove oil, foreign matter, and the like. Then, groove 11 is formed in stainless steel surface 10, extending to the interface between stainless steel surface 10 and plastic surface 20. For example, groove 11 can be formed using CNC machining.

[0048] S102, film layer production: forming a composite film layer including a nickel layer and a silver layer, or a composite film layer including a nickel layer and a gold layer, on the surface of the stainless steel in the area located in the groove, and the surface of the composite film layer is lower than the plastic surface.

[0049] See also Figure 4 , Figure 4 This is a schematic diagram of the housing after the composite film layer is formed. Because silver paste has poor adhesion to stainless steel and the contact resistance between the two is too high, in this embodiment, a composite film layer 30 comprising a nickel layer 32 and a silver layer 33 is first formed on the stainless steel surface 10 in the area located in the groove 11. The surface of the composite film layer 30 is lower than the plastic surface 20. It should be noted that the silver layer 33 can be replaced by a gold layer.

[0050] Nickel layer 32 acts as a transition layer, enhancing bonding strength, preventing diffusion of elements within the stainless steel (e.g., Fe, Cr), and improving surface properties. It also provides a more active surface for the subsequent formation of silver layer 33 or gold layer. Silver layer 33 or gold layer provides a soldering base, enhancing solder adhesion. For example, nickel layer 32, silver layer 33, and gold layer can all be fabricated using a physical vapor deposition (PVD) process.

[0051] Preferably, the composite film layer 30 may further include: a chromium layer 31 formed on the surface of the groove 11, that is, the chromium layer 31 is located below the nickel layer 32. The chromium layer 31 can enhance the corrosion resistance of the stainless steel surface 10, thereby improving the reliability of the shell.

[0052] As an example, the thickness of the chromium layer 31 may be 0.1-0.3 μm, the thickness of the nickel layer 32 may be 2-4 μm, the thickness of the silver layer 33 may be 1-3 μm, and the thickness of the gold layer may be 0.2-0.5 μm.

[0053] S103, tinning: forming a tin soldering layer on the surface of the composite film layer, and the tin soldering layer is substantially flush with the plastic surface.

[0054] See also Figure 5 , Figure 5This is a schematic diagram of the shell after the tin soldering layer is made. The tin soldering layer 40 can be made on the surface of the composite film layer 30, and the tin soldering layer 40 is basically flush with the plastic surface 20, that is, the tin soldering layer 40 fills the groove 11.

[0055] As an example of a tinning step, tinning may include:

[0056] A tin layer is coated on the surface of the composite film layer 30. The tin layer is preferably low-temperature tin with a melting point of 135-145°C, more preferably low-temperature tin wire with a melting point of 138-140°C. The coating thickness of the tin layer can be 80-140 μm to ensure uniform coverage of the composite film layer 30.

[0057] The tin layer is then hot-pressed at 145-185°C and a pressure of 5-10 N / mm2 to form a tin soldering layer 40. The tin soldering layer 40 and the silver layer 33 (or gold layer) form a Sn-Ag (Sn-Au) alloy layer to enhance interfacial bonding strength, and the tin soldering layer 40 is substantially flush with the plastic surface 20.

[0058] After the tin soldering layer 40 is completed, the surface of the tin soldering layer 40 may be cleaned. As some examples, dry ice cleaning, alcohol ultrasonic cleaning, sodium hydroxide solution cleaning, etc. may be used to remove residual flux on the surface and ensure the cleanliness of the tin surface, for example, a cleanliness of ≥99.5%.

[0059] S104, silver paste printing: printing a silver paste pattern on the surface of the tin soldering layer and the plastic surface, and curing them to obtain the PDS antenna.

[0060] See also Figure 6 , Figure 6 This diagram shows the housing after printing a silver paste pattern. After the tin solder layer 40 fills the groove 11, a silver paste pattern 50 (i.e., a PDS antenna pattern) can be printed on the surface of the tin solder layer 40 and the plastic surface 20. Specifically, the silver paste pattern 50 is printed on the housing surface, spanning the tin solder layer 40 (above the stainless steel surface 10) and the plastic surface 20. The pattern is then cured to form the PDS antenna. For example, the silver paste can be baked at 150°C for 1 hour to fully cure.

[0061] The method for fabricating a PDS antenna in this embodiment forms a composite film layer 30 on a stainless steel surface 10. The nickel layer 32 provides excellent bonding to the stainless steel and provides a more active surface for the silver layer 33 or gold layer. The silver layer 33 or gold layer provides a soldering base for the tin solder layer 40, improving solder adhesion. Finally, a silver paste pattern (i.e., the PDS antenna pattern) 50 is printed and cured, completing the fabrication of the PDS antenna. The tin solder layer 40 provides improved bonding to the composite film layer 30, indirectly improving the bonding between the PDS antenna and the stainless steel surface 10. Furthermore, conventional PDS antennas fabricated using this method often suffer from excessive contact resistance between the PDS antenna and the stainless steel surface. This embodiment can also reduce this contact resistance.

[0062] It should be noted that the composite film layer 30 can be formed directly in the stainless steel groove 11 by a coating method, but this method requires shielding and protecting other areas that do not require coating (for example, coating the plastic surface 20 with a protective glue for protection), and will waste coating materials and be costly. This embodiment of the present application provides another method for forming the composite film layer 30, please refer to Figure 7 , Figure 7 : is a partial cross-sectional schematic diagram of another housing after forming a PDS antenna provided by an embodiment of the present application. The method may specifically include:

[0063] A stainless steel sheet 12 is provided, and a composite film layer 30 is formed on the surface of the stainless steel sheet 12. The side of the stainless steel sheet 12 facing away from the composite film layer 30 is then welded to the groove 11. For example, laser welding can be used, and the laser pulse width can be 50-100ns and the power can be 30-50W. For example, the composite film layer 30 can be formed on a large stainless steel sheet, which can then be cut into stainless steel sheets 12 of a target size. Finally, laser welding is performed to weld the stainless steel sheet 12 to the groove 11, thereby completing the purpose of forming the composite film layer 30 on the stainless steel surface 10.

[0064] In the process of forming the composite film layer 30 in this embodiment, no masking is required, the process is simple, and the utilization rate of the coating material is 100% except for normal process loss, which can reduce costs.

[0065] In one embodiment, the PDS silver paste used in the silver paste printing step is of the first viscosity, and the tinning step may further include an ink filling step. For example, a PDS silver paste of the second viscosity may be set at the junction between the tin soldering layer 40 and the plastic by a dispensing device, and pre-baked, for example, at 80-100°C for 5-10 minutes. The second viscosity is less than the first viscosity. That is, the silver paste in the printing step uses a high-viscosity silver paste, and the ink filling step uses a low-viscosity silver paste. Since there is a gap at the interface between the tin soldering layer and the plastic, by setting the PDS silver paste of the second viscosity at the junction, the gap can be better backfilled, thereby avoiding the silver paste pattern from being broken at the gap, thereby improving the production yield and reliability of the PDS antenna.

[0066] As an example, the viscosity of high-viscosity silver paste can be 4-6 Pa·s, and the viscosity of low-viscosity silver paste can be 2-3 Pa·s (25°C, rotational viscometer LV-3, rotor No. 21, rotor speed of 10 rpm, tested after 1 minute of pre-shearing).

[0067] As an example of low-viscosity silver paste, the paste has solid particles ≤10μm in size, 85% silver content, and 15% epoxy resin. Its viscosity is 2Pa·s. A precision dispensing machine can fill the gap to a height slightly higher than the plastic surface, 0.05mm, to ensure complete coverage.

[0068] In one embodiment, the plastic is polyphenylene sulfide (PPS, optionally containing 40% glass fiber). Prior to the tinning step, a surface etching step may be performed: the plastic surface 20 is laser etched to a roughness of Ra 0.5-1.2 μm. The silver paste is preferably epoxy-based, which allows for a more stable bond with the PPS.

[0069] PPS is a non-polar polymer with low surface energy and low roughness (Ra≤0.2μm). The main force between PPS and PDS silver paste is van der Waals force. Silver paste that relies solely on van der Waals force for adhesion has insufficient adhesion (the hundred-grid test is usually ≤2B) and cannot meet high reliability requirements. To address this problem, this embodiment can modify the PPS surface and perform laser etching on the PPS surface to increase the mechanical anchoring force of the silver paste on the PPS surface; in addition, laser etching can break the CSC bonds in the PPS molecular chain to generate polar functional groups such as CO, C=O, and SO, thereby increasing the surface energy from approximately 35mN / m to 55-65mN / m, increasing the chemical bond sites with the silver paste, and thus improving the adhesion of the silver paste to the PPS surface. The principle is as follows:

[0070] (1) The PPS main chain breaks under the action of laser to generate free radicals.

[0071]

[0072] (2) Free radicals are oxidized in the air to generate polar oxygen-containing groups, such as sulfonic acid (-SO3H), carboxyl (-COOH), hydroxyl (-OH), etc.

[0073]

[0074] (3) The interfacial reaction between the silver paste and the modified PPS can be caused by one or more of the following methods:

[0075] A. Hydrogen bonding

[0076]

[0077] B. Sulfonic acid group and epoxy group

[0078]

[0079] C. Carboxyl and epoxy groups

[0080]

[0081] D. Hydroxyl and epoxy groups

[0082] .

[0083] In one embodiment, the laser used for PPS surface etching has a wavelength of 355 nm, a power of 5-15 W, a frequency of 20-50 kHz, and a scanning speed of 50-200 mm / s, which can form a three-dimensional microstructure with a roughness of Ra 0.5-1.2 μm on the PPS surface, thereby improving the mechanical anchoring force.

[0084] The present application will be further described below with reference to specific embodiments.

[0085] 1. Sample production

[0086] (1) A groove is made on the stainless steel surface of the injection molded part (the material is 316L stainless steel and PPS containing 40% glass fiber). The size of the groove is 2*2*0.25mm.

[0087] (2) Use plasma cleaning process to clean the surface of injection molded parts.

[0088] (3) A nickel layer (3 μm thick) and a gold layer (0.3 μm thick) were sequentially plated on a 316L stainless steel sheet (0.06 mm thick) by physical vapor deposition, and a 2*2 mm stainless steel sheet was cut.

[0089] (4) A 2*2 mm stainless steel sheet was welded in the groove with the coating facing up by laser welding (pulse width 75 ns, power 40 W).

[0090] (5) Coat the surface of the groove with a tin layer with a thickness of approximately 80 μm, ensuring uniform coverage of the silver layer at the bottom.

[0091] (6) Hot pressing is performed at 165°C and 8N / mm² to form a Sn-Ag alloy layer between the tin solder layer and the silver layer.

[0092] (7) Pulsed ultraviolet laser was used to etch the PPS surface. The laser wavelength was 355nm, the power was 10W, the frequency was 35kHz, and the scanning speed was 100mm / s. The morphology of the PPS surface before and after laser etching is shown in Figure 2. Figure 8 As shown, (a) is the morphology before etching, and (b) is the morphology after etching. The roughness is greatly improved after etching.

[0093] (8) Clean the entire surface of the substrate using sodium hydroxide solution.

[0094] (9) Apply silver paste (viscosity 2 Pa·s) at the junction of the tin solder layer and PPS, and pre-bake at 90°C for 8 minutes to allow the silver paste to initially solidify.

[0095] (10) PDS silver paste (epoxy system resin base) was printed on the surface of the tin solder layer and the PPS surface by pad printing process, and the silver paste film thickness was controlled to 12 μm. The film was baked at 150 ° C for 1 hour to completely solidify the silver paste and form an antenna pattern.

[0096] 2. Testing and Result Analysis

[0097] (1) Adhesion strength test: PC rods were bonded to 2×2mm silver paste using 511 glue and vertical pull-out test was performed. The test value was 3.2kgf, which met the requirement of ≥2.5kgf.

[0098] (2) 100-grid test: The silver paste was directly printed on the PPS sample without laser etching. The result of the 100-grid test was 2B (the standard for grid peeling, the larger the value, the better the adhesion), and the pull-out force was 0.6kgf. The result of the 100-grid test of the sample in this embodiment was 4B, and the pull-out force was 2.8kgf, which proved that the adhesion of the silver paste was greatly improved.

[0099] (3) Gap detection (interface between PPS and tin solder layer) and microscopic observation showed that the gap filling rate was 100% and no silver paste breakage occurred after boiling.

[0100] (4) Dyne value (surface energy) detection: the dyne value of the PPS surface increased from 32 to 34 dyne / cm, and the surface energy was significantly improved.

[0101] (5) Reliability test. The test conditions and results are shown in Table 1. Among them, "double 85" means: 85℃±2℃ temperature and 85%±3% humidity for 168 hours; "high temperature" means: 70℃±2℃ temperature for 168 hours; "low temperature" means: -40℃±2℃ temperature for 168 hours; "warm shock" means: temperature conversion between -40±2℃ / 1 hour and 70±2℃ / 1 hour, the conversion time is less than 30 seconds, and 12 cycles are stored.

[0102] Table 1 Contact resistance measured before and after reliability test (mΩ)

[0103]

[0104] The test results show that the contact resistance of the sample without the composite film layer fluctuates greatly due to poor adhesion. However, the contact resistance of the sample of this embodiment is small and stable, and after the reliability test, the contact resistance is almost unchanged.

[0105] The present application also provides an electronic device, comprising a housing and a PDS antenna. The inner surface of the housing comprises a stainless steel surface 10 and a plastic surface 20. The PDS antenna is formed on the stainless steel surface 10 and the plastic surface 20 and is formed using any of the manufacturing methods described in the above embodiments. As some examples, the electronic device may be a mobile phone, a tablet, or other device.

[0106] For other manufacturing principles and processes of the electronic device of this embodiment, please refer to the description of the manufacturing method of the PDS antenna in the aforementioned embodiment of the present invention, which will not be repeated here.

[0107] It should be understood that the terms "comprising" and "including" indicate the presence of the described features, steps, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms "or", "and / or", "including at least one of the following", etc. used in this application may be interpreted as inclusive, or mean any one or any combination. For example, "including at least one of the following: A, B, C" means "any one of the following: A; B; C; A and B; A and C; B and C; A and B and C", and for another example, "A, B or C" or "A, B and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A and B and C". Exceptions to this definition will only occur when the combination of elements, functions, steps or operations are inherently mutually exclusive in some way.

[0108] It should be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are merely used to distinguish information of the same type from one another. For example, first information could also be referred to as second information, and similarly, second information could also be referred to as first information without departing from the scope of this document. Depending on the context, as used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context indicates otherwise.

[0109] It should be understood that the orientations or positional relationships indicated by terms such as "top", "bottom", "up", "down", "vertical", and "horizontal" are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0110] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. The various technical features of the technical solution of the present application can be arbitrarily combined. In order to make the description concise, all possible combinations of the various technical features in the above embodiments are not described. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, as long as there is no contradiction in the combination of these technical features, are also included in the patent protection scope of the present application.

Claims

1. A method for manufacturing a PDS antenna, characterized in that: The carrier of the PDS antenna includes a stainless steel surface and a plastic surface, and the manufacturing method includes: Groove making: making a groove on the stainless steel surface, wherein the groove extends to the junction of the stainless steel surface and the plastic surface; Film layer production: providing a large-sized stainless steel sheet; forming a composite film layer including a nickel layer and a silver layer, or a composite film layer including a nickel layer and a gold layer, on the surface of the large-sized stainless steel sheet; cutting the large-sized stainless steel sheet into stainless steel sheets of a target size; welding the surface of the stainless steel sheet of the target size facing away from the composite film layer to the groove, with the surface of the composite film layer being lower than the surface of the plastic; Tinning: forming a tin soldering layer on the surface of the composite film layer, and the tin soldering layer is flush with the plastic surface; Silver paste printing: printing a silver paste pattern on the surface of the tin soldering layer and the plastic surface, and curing the silver paste to obtain the PDS antenna.

2. The production method according to claim 1, characterized in that The tinning step comprises: coating a tin layer on the surface of the composite film layer; At 145~185℃, pressure 5~10N / mm 2 The tin layer is hot-pressed under conditions of to obtain the tin soldering layer.

3. The production method according to claim 1, characterized in that In the silver paste printing step, a PDS silver paste with a first viscosity is used; The tinning step further includes: Filling ink: PDS silver paste with a second viscosity is provided at the interface between the tin soldering layer and the plastic, wherein the second viscosity is less than the first viscosity.

4. The production method according to claim 3, characterized in that: The first viscosity is 4-6 Pa·s, and the second viscosity is 2-3 Pa·s.

5. The production method according to claim 1, characterized in that: The thickness of the nickel layer is 2-4 μm; and / or, The thickness of the silver layer is 1-3 μm; and / or, The thickness of the gold layer may be 0.2-0.5 μm.

6. The production method according to any one of claims 1 to 5, characterized in that: The plastic is polyphenylene sulfide; Before the tinning step, the method further comprises: Surface etching: performing laser etching on the plastic surface to make the roughness of the plastic surface Ra0.5~1.2μm.

7. The production method according to claim 6, characterized in that: The laser has a wavelength of 355 nm, a power of 5 to 15 W, a frequency of 20 to 50 kHz, and a scanning speed of 50 to 200 mm / s.

8. An electronic device, characterized in that: The invention comprises a shell and a PDS antenna, wherein the inner surface of the shell comprises a stainless steel surface and a plastic surface, and the PDS antenna is formed on the stainless steel surface and the plastic surface, and is formed by the manufacturing method according to any one of claims 1 to 7.

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