Packaging structure and method of broadband conical inductor with planarized return loss

Abstract

The invention relates to the technical field of electronic circuits and communication, in particular to a packaging structure and method of a broadband conical inductor with flattened return loss, and the packaging structure comprises an S-shaped cover shell structure, one side surface of the S-shaped cover shell structure is provided with a slope surface, a conical inductor is arranged above the slope surface, and the conical inductor is arranged in the S-shaped cover shell structure. And the surface of one side of the S-shaped cover shell structure is fixedly connected with an adhesive. The packaging structure and method for the broadband conical inductor with the planarized return loss have the advantages that packaging is simplified, the mounting requirement is met, the technology is simplified, the small-size packaging problem is solved, environmental interference can be resisted, the nickel-gold layer is plated, the welding spot strength is ensured, the angle of the inductor is fixed through cooperation of the adhesive and the slope, and the packaging effect is good. The distance between the cover shell and the microwave waveguide is ensured, the pin welding position is reasonable, the high-frequency performance is optimized, the return loss is reduced, the port matching degree is improved, selected materials are excellent, and the cover shell is made of special materials and is beneficial to production.

Description

Technical Field

[0001] The present invention relates to the field of electronic circuits and communication technology, and in particular to a packaging structure and method of a broadband conical inductor with flattened return loss. Background Art

[0002] The characteristic of conical inductors is that they have good consistency in a wide frequency band. They are widely used in DC bias circuits, amplifier circuits, and optical wireless communication systems, including broadband low-noise amplifiers, lithium niobate electro-optic modulators, analog direct-modulated lasers, external Bias-Tee devices, and other high-frequency devices and modules.

[0003] (1) It has a very high quality factor and low self-inductance in high-frequency and broadband circuits, so it can be used to design filters with high quality factors. For example, conical inductors and capacitors can be combined to form high-pass, low-pass, band-pass and band-stop filters;

[0004] (2) Used to match the impedance of a circuit. For example, in antenna design, a conical inductor can be used as a matching network to match the impedance of the antenna to the impedance of a radio transmitter or receiver.

[0005] (3) Used to design oscillator circuits. For example, in radio frequency circuits, conical inductors can be combined with components such as capacitors and transistors to form oscillator circuits to generate high-frequency signals.

[0006] (4) Used in designing power amplifier circuits. For example, in radio communications, conical inductors can be combined with components such as transistors to form power amplifier circuits to amplify the power of radio signals.

[0007] Currently, there are the following problems in the packaging of conical inductors:

[0008] (1) The shape of the conical inductor itself is conical and irregular, and its pin lines are at the small end and the bottom end respectively. Therefore, it is limited in industrial and large-scale applications and cannot meet the surface mounting requirements of integrated circuits;

[0009] (2) Passive electronic components benefit from the popularity of consumer electronic products such as smartphones, tablets, and automotive electronics, as well as the rapid development of emerging technologies such as 5G, the Internet of Things, and artificial intelligence. The market demand for passive components continues to grow. In order to meet the needs of thin, short, and high-performance electronic products, the thinning, miniaturization, and integration of packaging structures have become an important trend in the development of passive component technology;

[0010] (3) Conical inductors are broadband inductors that can be used in high-frequency microwave circuits from 40G to 100G. The high levels of RF and microwave power in microwave circuits are invisible and difficult to detect, and can generate incredible RF radiation and heat in a small range. Therefore, suppressing the impact of RF radiation on the circuit and meeting heat dissipation requirements are necessary conditions for the design of passive component packaging structures;

[0011] (4) The pin wires of the conical inductor, especially the pin wires at the small end, are closely related to the loss of its applicable frequency. The conical inductor has strict requirements on the installation of the pin wires.

[0012] (5) During the packaging process, due to the complexity of the packaging process, such as material selection, processing accuracy, assembly error and other factors, inaccurate angle and distance control may lead to poor electromagnetic coupling, reduced signal transmission quality, and may even cause electromagnetic interference or signal distortion. Summary of the invention

[0013] The object of the present invention is to provide a packaging structure and method for a broadband tapered inductor with flattened return loss, so as to solve the problems raised in the above background technology.

[0014] To achieve the above-mentioned object, the present invention provides the following technical solution: a packaging structure of a broadband conical inductor with flattened return loss, comprising an S-shaped cover shell structure 1, a slope 2 is provided on one side surface of the S-shaped cover shell structure 1, a conical inductor 3 is arranged above the slope 2, an adhesive 4 is fixedly connected to one side surface of the S-shaped cover shell structure 1, a lead wire 5 is fixedly connected to one side surface of the conical inductor 3, a copper metal layer 6 is fixedly connected to the upper surface of one side surface of the S-shaped cover shell structure 1, a nickel-plated layer 7 is fixedly connected to the upper surface of the copper metal layer, and a gold-plated layer 8 is fixedly connected to the upper surface of the nickel-plated layer 7;

[0015] Preferably, an angled slope is integrated into the interior of the S-shaped housing, and the preset inclination angle of the slope can ensure that the angle between the central axis of the conical inductor and the signal line is fixed within the range of 15-75°.

[0016] Preferably, the copper metal layer 6, the nickel-plated layer 7 and the gold-plated layer 8 are arranged in a group on the left and right sides of the upper surface of the S-shaped cover shell structure 1, the sizes of the copper metal layer 6, the nickel-plated layer 7 and the gold-plated layer 8 are consistent, and the pin line 5 is welded to the gold-plated layer 8.

[0017] A packaging structure of a broadband tapered inductor with flattened return loss, further comprising the following steps:

[0018] S1. Preliminary preparation: clean the S-shaped housing, select the appropriate conical inductor and check the electrical performance;

[0019] S2. Use adhesive to fix the conical inductor in the S-shaped housing, with the small end facing down close to the bottom, and use a micro-clamp to adjust the position;

[0020] S3, pull the lead wire, pre-treat it with flux, and spot weld it on the side wall of the nickel-plated gold layer. Strictly control the welding parameters and monitor the solder joints with a microscope.

[0021] S4. Set the reflow temperature curve according to the characteristics of the S-shaped shell, solder, and circuit board. Use the reflow process with the solder layer to solder the package cover to the circuit board, and pay attention to the fit;

[0022] S5. After packaging, use a vector network analyzer and X-ray detection equipment to detect return loss, internal solder joints, etc.

[0023] Preferably, the specific method of the steps of S1, preliminary preparation, cleaning the S-shaped housing, selecting and adapting the conical inductor and checking the electrical performance is as follows:

[0024] The S-shaped shell with integrated angled slope is thoroughly cleaned to remove dust, oil and other impurities that may exist on the surface, ensuring that the environment inside the cavity is clean and tidy, providing a good foundation for the subsequent installation of the conical inductor. At the same time, a conical inductor of appropriate specifications is selected, and its electrical performance parameters are carefully checked according to the design requirements to ensure that it meets the application scenario requirements of the overall packaging structure.

[0025] Preferably, the specific method of the step of pulling the lead wire in S3, spot welding it on the side wall of the nickel-plated gold layer after pre-treatment with flux, strictly controlling the welding parameters, and monitoring the solder joints with a microscope is as follows:

[0026] S3-1. Select appropriate spot welding equipment and flux, and evenly apply the flux to the lead wires of the conical inductor and the nickel-gold layer on the free end surface of the side wall of the S-shaped shell to remove the oxide layer on the metal surface, enhance the wettability of the solder, and lay a good foundation for subsequent spot welding operations;

[0027] S3-2, accurately set the welding current between 30-35mA, and adjust and lock the welding time at 0.1-0.2 seconds to ensure that the solder melts quickly when the lead wire contacts the nickel-plated gold layer, forming a stable metal bond and effectively avoiding problems such as excessive oxidation of the solder and brittle solder joint structure caused by too long a time. Then adjust the pressure of the welding equipment to 0.2-0.3N. This pressure value can just make the lead wire and the nickel-plated gold layer fit closely, ensure that the solder is evenly distributed between the two, and ensure the quality of the solder joint;

[0028] S3-3. Use tweezers or professional pulling tools to pull the pins at both ends of the conical inductor to align them accurately and fit them on the free end faces of the corresponding nickel-plated gold layer. Keep your hands stable during the process to avoid the pins from shifting or shaking, which will affect the spot welding accuracy. Then start the spot welding equipment and perform welding according to the preset parameters. At the moment of welding, pay close attention to the changes at the solder joints, observe the melting, flow and solidification of the solder, and ensure that the solder joints are full and smooth, without defects such as cold solder joints and solder penetration.

[0029] S3-4. After spot welding is completed, the quality of the solder joints and the electrical connection performance of the solder joints shall be monitored in real time to ensure that a good conductive path is formed between the pin wire and the nickel-plated gold layer to meet the electrical design requirements of the product. If the quality of the solder joints is found to be substandard, they shall be marked and reworked in a timely manner.

[0030] Preferably, in S4, a reflow temperature curve is set according to the characteristics of the S-shaped housing, solder, and circuit board, and the package cover is soldered to the circuit board using a reflow process in conjunction with a solder layer, and the specific method in the step of paying attention to the lamination condition is as follows:

[0031] S4-1. Carefully study the material properties of the S-shaped shell, deeply understand the solder properties and fully grasp the information such as the material, number of layers and circuit layout of the circuit board;

[0032] S4-2, start setting the temperature curve according to the analyzed data;

[0033] S4-3. According to the set reflow soldering temperature curve, the package cover shell structure integrated with the angled conical inductor is flow soldered, and the solder layer undergoes melting, wetting, and solidification in sequence under temperature changes.

[0034] Preferably, the specific method of starting to set the temperature curve step according to the analyzed data in S4-2 is as follows:

[0035] The temperature curve is divided into preheating zone, insulation zone, reflow zone and cooling zone. The temperature of the preheating zone is set between 100℃-150℃, and the time is controlled at 60-120 seconds. In this stage, the temperature of the component is slowly increased to allow the S-shaped shell, solder and circuit board to be evenly heated, and the internal water vapor is gradually discharged to reduce thermal shock. The temperature of the insulation zone is set within the range of 10℃-20℃ below the melting point of the solder, and the time is maintained for 30-60 seconds. In this range, the solder begins to soften and gradually reaches a uniform melting state to ensure that the solder joint can be quickly wetted when entering the reflow zone to form a good metal connection. The temperature of the reflow zone needs to be 20℃-30℃ higher than the melting point of the solder, usually set at 200℃-240℃, and the time is 20-40 seconds. In this stage, the solder is fully melted and quickly wets the solder joint under the action of capillary force, filling the gap between the pin line and the circuit board pad to achieve reliable electrical connection. The cooling zone adopts a rapid cooling method to reduce the temperature to below 100°C within 30-60 seconds, which promotes the rapid solidification of the solder, fixes the solder joint structure, and ensures the welding quality.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. This device eliminates the inductor package substrate commonly used in microwave circuit applications, directly glues the conical inductor on the slope of the integrated angled cover structure, and directly welds the package cover to the circuit board, which can not only meet the requirements of the mounting process, but also simplify the packaging operation process, solve the packaging in a small space, and effectively protect it from interference from the external environment;

[0038] 2. A nickel-gold layer is plated on the free end surface of the integrated angled cover structure through chemical nickel plating and electroplating gold process, which can effectively prevent the oxidation of the copper metal layer, break through the height limit of the package cover structure, and ensure that the solder joint has sufficient strength;

[0039] 3. Placing the conical inductor directly on the cover structure with a preset slope angle can ensure that the angle between the central axis of the conical inductor and the signal line is fixed within the range of 15-75°. In the installation process of the conical inductor, the appropriate distance between the end face of the small end and the microwave transmission waveguide is ensured, and the pin line of the small end should be welded as close as possible to the microwave transmission waveguide. By modeling different angles and distances between the conical inductor and the microwave waveguide, it is calculated that as the angle with the signal line increases and the distance decreases, the return loss S11 of the S parameter in the frequency range of 20GHz-45GHz will be further flattened, and the matching degree of its port will also increase accordingly. Not only that, in high-frequency circuits, the conical inductor maintains this specific installation angle to increase the flatness of the inductor return loss, thereby improving the flattening compensation of the amplified signal in the bias power supply unit of the conical inductor, thereby enhancing the availability of the amplified signal. At the same time, the shell structure can optimize its impedance matching, reduce electromagnetic interference, improve thermal performance and ensure structural stability, which helps to improve the performance and reliability of conical inductors in high-frequency circuits;

[0040] 4. The cover shell structure made of alumina ceramics, silicon carbide ceramics, resin or plastic is integrated with an angled slope, which has the characteristics of heat resistance and heat insulation, light weight, good insulation performance, high hardness, not easy to be corroded, and good heat dissipation and shielding properties;

[0041] 5. The integrated angled cover shell structure has good stability and strong practicality, and provides a good foundation for subsequent automated mounting production, enabling the conical inductor to be widely used in large-scale and industrial markets. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of a cover packaging structure of an integrated angled tapered inductor in the present invention;

[0043] Figure 2 A schematic diagram of the nickel-gold layer plated at the bottom of the free end surface of the patent of the present invention;

[0044] Figure 3 A schematic diagram of the nickel-gold layer plated at the bottom of the free end surface of the patent of the present invention;

[0045] Figure 4 The relationship between the return loss S11 and the frequency of the tapered inductor at different angles, and the flattening degree of the return loss caused by the tapered inductor;

[0046] Figure 5 Schematic diagram of the model for different distances between the tapered inductor and the microwave waveguide;

[0047] Figure 6Figure 3 is a graph showing the relationship between the return loss S11 and frequency of a conical inductor at different distances.

[0048] In the figure: 1. S-shaped cover structure, 2. slope, 3. conical inductor, 4. adhesive, 5. lead wire, 6. copper metal layer, 7. nickel plating layer, 8. gold plating layer. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Example 1

[0051] See also Figure 1-6 , a packaging structure of a broadband conical inductor with flattened return loss, comprising an S-shaped cover shell structure 1, a slope 2 is provided on one side surface of the S-shaped cover shell structure 1, a conical inductor 3 is arranged above the slope 2, an adhesive 4 is fixedly connected to one side surface of the S-shaped cover shell structure 1, a lead wire 5 is fixedly connected to one side surface of the conical inductor 3, a copper metal layer 6 is fixedly connected to the upper surface of one side surface of the S-shaped cover shell structure 1, a nickel-plated layer 7 is fixedly connected to the upper surface of the copper metal layer, and a gold-plated layer 8 is fixedly connected to the upper surface of the nickel-plated layer 7;

[0052] Furthermore, an angled slope 2 is integrated inside the S-shaped shell. The preset inclination angle of the slope 2 can ensure that the angle between the central axis of the conical inductor 3 and the signal line is fixed in the range of 15-75°. Through the setting of the slope 2 and the conical inductor 3, when in use, the angle is stabilized to reduce magnetic field coupling and adapt to high-frequency communication; at the signal transmission level, the coupling is optimized, and the signal is efficiently transmitted within a wide frequency to meet high bandwidth requirements; during packaging, precise positioning is used to improve efficiency and reduce scrap rate; in terms of heat dissipation, the channel is optimized to extend the life of high-power devices.

[0053] Furthermore, a group of the copper metal layer 6, the nickel-plated layer 7 and the gold-plated layer 8 are arranged on the left and right sides of the upper surface of the S-shaped cover shell structure 1, and the sizes of the copper metal layer 6, the nickel-plated layer 7 and the gold-plated layer 8 are consistent, and the pin line 5 is welded and connected to the gold-plated layer 8. The arrangement of the copper metal layer 6, the nickel-plated layer 7 and the gold-plated layer 8 has many benefits. In terms of electrical connection, the gold-plated layer 8 is resistant to oxidation and has strong conductivity, which ensures the welding reliability of the pin line 5 and is suitable for high-frequency signal transmission; the nickel-plated layer 7 enhances adhesion and stabilizes the plating structure; the copper metal layer 6 provides a good foundation, and the three work together to improve the overall performance and life.

[0054] Embodiment 2:

[0055] A method for packaging a broadband conical inductor with flattened return loss, using the packaging device of the flattened broadband conical inductor in embodiment 1, further comprising the following steps:

[0056] S1. Preliminary preparation: clean the S-shaped housing, select the appropriate conical inductor and check the electrical performance;

[0057] The S-shaped shell with an integrated angled slope is thoroughly cleaned to remove dust, oil and other impurities that may exist on the surface, ensuring that the cavity environment is clean and tidy, providing a good foundation for the subsequent installation of the conical inductor. At the same time, the conical inductor of appropriate specifications is selected, and its electrical performance parameters are carefully checked according to the design requirements to ensure that it meets the application scenario requirements of the overall packaging structure.

[0058] S2. Use adhesive to fix the conical inductor in the S-shaped housing, with the small end facing down close to the bottom, and use a micro-clamp to adjust the position;

[0059] S3, pull the lead wire, pre-treat it with flux, and spot weld it on the side wall of the nickel-plated gold layer. Strictly control the welding parameters and monitor the solder joints with a microscope.

[0060] S3-1. Select appropriate spot welding equipment and flux, and evenly apply the flux to the lead wires of the conical inductor and the nickel-gold layer on the free end surface of the side wall of the S-shaped shell to remove the oxide layer on the metal surface, enhance the wettability of the solder, and lay a good foundation for subsequent spot welding operations;

[0061] S3-2, accurately set the welding current between 30-35mA, and adjust and lock the welding time at 0.1-0.2 seconds to ensure that the solder melts quickly when the lead wire contacts the nickel-plated gold layer, forming a stable metal bond and effectively avoiding problems such as excessive oxidation of the solder and brittle solder joint structure caused by too long a time. Then adjust the pressure of the welding equipment to 0.2-0.3N. This pressure value can just make the lead wire and the nickel-plated gold layer fit closely, ensure that the solder is evenly distributed between the two, and ensure the quality of the solder joint;

[0062] S3-3. Use tweezers or professional pulling tools to pull the pins at both ends of the conical inductor to align them accurately and fit them on the free end faces of the corresponding nickel-plated gold layer. Keep your hands stable during the process to avoid the pins from shifting or shaking, which will affect the spot welding accuracy. Then start the spot welding equipment and perform welding according to the preset parameters. At the moment of welding, pay close attention to the changes at the solder joints, observe the melting, flow and solidification of the solder, and ensure that the solder joints are full and smooth, without defects such as cold solder joints and solder penetration.

[0063] S3-4. After spot welding is completed, the quality of the solder joints and the electrical connection performance of the solder joints shall be monitored in real time to ensure that a good conductive path is formed between the pin wire and the nickel-plated gold layer to meet the electrical design requirements of the product. If the quality of the solder joints is found to be substandard, they shall be marked and reworked in a timely manner.

[0064] S4. Set the reflow temperature curve according to the characteristics of the S-shaped shell, solder, and circuit board. Use the reflow process with the solder layer to solder the package cover to the circuit board, and pay attention to the fit;

[0065] S4-1. Based on the research on the material properties of the S-shaped shell, combined with the solder properties, we can fully grasp the information such as the material, number of layers and circuit layout of the circuit board;

[0066] S4-2, start setting the temperature curve according to the analyzed data;

[0067] The temperature curve is divided into preheating zone, insulation zone, reflow zone and cooling zone. The temperature of the preheating zone is set between 100℃-150℃, and the time is controlled at 60-120 seconds. In this stage, the temperature of the component is slowly increased to allow the S-shaped shell, solder and circuit board to be evenly heated, and the internal water vapor is gradually discharged to reduce thermal shock. The temperature of the insulation zone is set within the range of 10℃-20℃ below the melting point of the solder, and the time is maintained for 30-60 seconds. In this range, the solder begins to soften and gradually reaches a uniform melting state to ensure that the solder joint can be quickly wetted when entering the reflow zone to form a good metal connection. The temperature of the reflow zone needs to be 20℃-30℃ higher than the melting point of the solder, usually set at 200℃-240℃, and the time is 20-40 seconds. In this stage, the solder is fully melted and quickly wets the solder joint under the action of capillary force, filling the gap between the lead wire and the circuit board pad to achieve reliable electrical connection. The cooling zone adopts a rapid cooling method to reduce the temperature to below 100°C within 30-60 seconds, which promotes the rapid solidification of the solder, fixes the solder joint structure, and ensures the welding quality.

[0068] S4-3, according to the set reflow soldering temperature curve, the package cover structure integrated with the angled tapered inductor is flow soldered, and the solder layer undergoes melting, wetting, and solidification in sequence under temperature changes;

[0069] S5. After packaging, use a network analyzer and X-ray detection equipment to detect return loss, internal solder joints, etc.

[0070] With the above structure, the working principle of this case is: in the packaging process, first enter the preliminary preparation stage, thoroughly clean the S-shaped shell with integrated angled slope, remove impurities, create a clean installation environment for the conical inductor, and select the appropriate conical inductor according to the design requirements and verify the electrical performance to ensure that the initial state of the component is good. Then, use adhesive to accurately fix the conical inductor in the S-shaped shell, with the small end facing down close to the bottom, and use a micro-clamp to fine-tune the position. Use the angled slope integrated in the S-shaped shell to stabilize the angle between the central axis of the conical inductor and the signal line at 15-75°, thereby increasing the flatness of the return loss of the conical inductor; this lays a precise spatial foundation for subsequent packaging The foundation can also reduce magnetic field coupling and adapt to high-frequency communication. Then comes the pin wire spot welding link. Select appropriate spot welding equipment and flux, pre-treat the pin wire and nickel-plated gold layer, remove the oxide layer to improve the wettability of the solder; accurately set the welding current, time, and pressure to ensure that the solder melts instantly and combines firmly to avoid bad problems; carefully pull the pin wire to spot weld on the side wall of the nickel-plated gold layer, monitor the quality of the solder joints in real time to ensure a good conductive path, and then finely set the reflow soldering temperature curve according to the characteristics of the S-shaped shell, solder, and circuit board. The temperature is precisely controlled in four zones: preheating, insulation, reflow, and cooling, so that the solder melts, wets, and solidifies in an orderly manner, and the package cover is stably welded to the circuit board. Pay close attention to the fitting during the process to ensure the welding quality. Finally, the packaging is completed, and the network analyzer and X-ray detection equipment are used to detect the return loss, internal solder joints, etc. The copper metal layer provides basic conductive support, the nickel plating layer enhances the adhesion of the plating, and the gold plating layer resists oxidation and ensures reliable soldering of the pins at high frequencies. The three work together to improve the overall performance and lifespan, and comprehensively guarantee the stable and efficient operation of the conical inductor in the electronic circuit and communication fields.

[0071] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A packaging structure of a broadband conical inductor with flattened return loss, comprising an S-shaped cover structure (1), characterized in that: A slope (2) is provided on one side surface of the S-shaped cover shell structure (1); a conical inductor (3) is arranged above the slope (2); an adhesive (4) is fixedly connected to one side surface of the S-shaped cover shell structure (1); a lead wire (5) is fixedly connected to one side surface of the conical inductor (3); a copper metal layer (6) is fixedly connected to the surface above one side surface of the S-shaped cover shell structure (1); a nickel-plated layer (7) is fixedly connected to the surface above the copper metal layer; and a gold-plated layer (8) is fixedly connected to the surface above the nickel-plated layer (7).

2. The packaging structure of a broadband tapered inductor with flattened return loss according to claim 1, characterized in that: The S-shaped housing structure (1) has an integrally formed angled slope (2) inside, and the preset inclination angle of the slope (2) can ensure that the angle between the central axis of the conical inductor (3) and the signal line is fixed within the range of 15-75°.

3. The packaging structure of a broadband tapered inductor with flattened return loss according to claim 1, characterized in that: The copper metal layer (6), the nickel-plated layer (7) and the gold-plated layer (8) are arranged in groups on the left and right sides of the upper surface of the S-shaped cover shell structure (1); the sizes of the copper metal layer (6), the nickel-plated layer (7) and the gold-plated layer (8) are consistent, and the lead wire (5) is connected to the gold-plated layer (8) by welding.

4. A packaging method for a broadband tapered inductor with flattened return loss, characterized in that: The packaging structure of a flattened broadband tapered inductor according to any one of claims 1 to 3 further comprises the following steps: S1. Preliminary preparation: clean the S-shaped housing, select the appropriate conical inductor and check the electrical performance; S2. Use adhesive to fix the conical inductor in the S-shaped housing, with the small end facing down close to the bottom, and use a micro-clamp to adjust the position; S3, pull the lead wire, pre-treat it with flux, and spot weld it on the side wall of the nickel-plated gold layer. Strictly control the welding parameters and monitor the solder joints with a microscope. S4. Set the reflow temperature curve according to the characteristics of the S-shaped shell, solder, and circuit board. Use the reflow process with the solder layer to solder the package cover to the circuit board, and pay attention to the fit; S5. After packaging, use a vector network analyzer and X-ray detection equipment to detect return loss, internal solder joints, etc.

5. The packaging method of a broadband tapered inductor with flattened return loss according to claim 4, characterized in that: The specific methods in the steps of S1, preliminary preparation, cleaning the S-shaped housing, selecting and adapting the conical inductor and checking the electrical performance are as follows: The S-shaped shell with integrated angled slope is thoroughly cleaned to remove dust, oil and other impurities that may exist on the surface, ensuring that the environment inside the cavity is clean and tidy, providing a good foundation for the subsequent installation of the conical inductor. At the same time, a conical inductor of appropriate specifications is selected, and its electrical performance parameters are carefully checked according to the design requirements to ensure that it meets the application scenario requirements of the overall packaging structure.

6. The packaging method of a broadband tapered inductor with flattened return loss according to claim 4, characterized in that: The specific method of the step of pulling the lead wire in S3, spot welding it on the side wall of the nickel-plated gold layer after pre-treatment with flux, strictly controlling the welding parameters, and monitoring the solder joints with a microscope is as follows: S3-1. Select appropriate spot welding equipment and flux, and evenly apply the flux to the lead wires of the conical inductor and the nickel-gold layer on the free end surface of the side wall of the S-shaped shell to remove the oxide layer on the metal surface, enhance the wettability of the solder, and lay a good foundation for subsequent spot welding operations; S3-2, accurately set the welding current between 30-35mA, and adjust and lock the welding time at 0.1-0.2 seconds to ensure that the solder melts quickly when the lead wire contacts the nickel-plated gold layer, forming a stable metal bond and effectively avoiding problems such as excessive oxidation of the solder and brittle solder joint structure caused by too long a time. Then adjust the pressure of the welding equipment to 0.2-0.3N. This pressure value can just make the lead wire and the nickel-plated gold layer fit closely, ensure that the solder is evenly distributed between the two, and ensure the quality of the solder joint; S3-3. Use tweezers or professional pulling tools to pull the pins at both ends of the conical inductor to align them accurately and fit them on the free end faces of the corresponding nickel-plated gold layer. Keep your hands stable during the process to avoid the pins from shifting and shaking, which will affect the spot welding accuracy. Then start the spot welding equipment and perform welding according to the preset parameters. At the moment of welding, pay close attention to the changes at the solder joints, observe the melting, flow and solidification of the solder, and ensure that the solder joints are full and smooth, without defects such as cold solder joints and solder penetration. S3-4. After spot welding is completed, the quality of the solder joints and the electrical connection performance of the solder joints shall be monitored in real time to ensure that a good conductive path is formed between the pin wire and the nickel-plated gold layer to meet the electrical design requirements of the product. If the quality of the solder joints is found to be substandard, they shall be marked and reworked in a timely manner.

7. The packaging method of a broadband tapered inductor with flattened return loss according to claim 4, characterized in that: In S4, a reflow temperature curve is set according to the characteristics of the S-shaped housing, solder, and circuit board, and the package cover is soldered to the circuit board using a reflow process in conjunction with a solder layer, and the specific method in the step of paying attention to the bonding condition is as follows: S4-1. Carefully study the material properties of the S-shaped shell, deeply understand the solder properties and fully grasp the information such as the material, number of layers and circuit layout of the circuit board; S4-2, start setting the temperature curve according to the analyzed data; S4-3. According to the set reflow soldering temperature curve, the package cover shell structure integrated with the angled conical inductor is flow soldered, and the solder layer undergoes melting, wetting, and solidification in sequence under temperature changes.

8. The packaging method of a broadband tapered inductor with flattened return loss according to claim 4, characterized in that: The specific method of starting to set the reflow soldering temperature curve step according to the analyzed data in S4-2 is as follows: The temperature curve is divided into preheating zone, insulation zone, reflow zone and cooling zone. The temperature of the preheating zone is set between 100℃-150℃, and the time is controlled at 60-120 seconds. In this stage, the temperature of the component is slowly increased to allow the S-shaped shell, solder and circuit board to be evenly heated, and the internal water vapor is gradually discharged to reduce thermal shock. The temperature of the insulation zone is set within the range of 10℃-20℃ below the melting point of the solder, and the time is maintained for 30-60 seconds. In this range, the solder begins to soften and gradually reaches a uniform melting state to ensure that the solder joint can be quickly wetted when entering the reflow zone to form a good metal connection. The temperature of the reflow zone needs to be 20℃-30℃ higher than the melting point of the solder, usually set at 200℃-240℃, and the time is 20-40 seconds. In this stage, the solder is fully melted and quickly wets the solder joint under the action of capillary force, filling the gap between the pin line and the circuit board pad to achieve reliable electrical connection. The cooling zone adopts a rapid cooling method to reduce the temperature to below 100°C within 30-60 seconds, which promotes the rapid solidification of the solder, fixes the solder joint structure, and ensures the welding quality.

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