Pin-free semiconductor integrated power module and terminal equipment

Abstract

The invention relates to the technical field of power semiconductors, in particular to a pin-free semiconductor integrated power module and terminal equipment, which comprises a shell and a substrate, the substrate comprises an insulating plate, a first metal layer and a second metal layer, the first metal layer and the second metal layer cover two opposite surfaces of the insulating plate, the shell is packaged on the substrate, the first metal layer faces the shell, and the second metal layer faces the shell. The first metal layer is provided with a connecting bonding pad on the outer side of the shell, the connecting bonding pad is used for being connected with an external PCB, and the surface of the connecting bonding pad is covered with a protective layer. The pin-free semiconductor integrated power module is directly connected with the outside through the connecting bonding pad, so that conductive paths are reduced, the reliability of electrical connection is improved, the risk of poor contact caused by pin dimensional tolerance, welding process deviation and the like is reduced, parasitic inductance and capacitance in a pin connection mode are improved, and the reliability of the power module is improved. Electrical parameters such as electromagnetic compatibility, a safe working area and the like of the power module are optimized, and stability and durability of the module in a high-vibration environment are enhanced at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of power semiconductors, and in particular to a pinless semiconductor integrated power module and a terminal device. Background Art

[0002] The power module uses a power chip and a certain electrical layout to output and control power through external pins. Existing power modules, regardless of the packaging form of the power module, such as QFP packaging module (quad flat package module), DPIM packaging (see patent CN220556592U), PIM power module (see patent CN216086502U), etc., all use power pins / terminals to perform internal and external power inversion and input / output to achieve internal and external electrical connections of the power module. After the power pins / terminals of the traditional DPIM packaging module and HPD packaging module are soldered and wired on the chip, the power pins / terminals are welded to the electrical layer substrate by soldering, ultrasonic bonding, etc. to achieve internal and external electrical connections of the power module. For package modules such as QFP package module (quad flat package module) and PIM power module (see CN216086502U), the manufacturing process requires the design of corresponding proprietary lead frames. After the chip is soldered, it is connected to the power pins / terminals by means of bonding wires and encapsulated with epoxy resin to complete the corresponding electrical functions.

[0003] Taking the DPIM power module as an example, it mainly includes a DBC substrate, a power chip, bonding wires, a power terminal and a plastic encapsulation colloid. The power pins are often welded to the DBC electrical layer where the chip is located through solder and / or welding sheets after the power chip is bonded and wired, or the power pins are directly bonded to the DBC electrical layer where the chip is located through ultrasonic bonding, thereby completing the installation of the "bridge" for internal and external communication of the power module, and then the power module is encapsulated using a plastic encapsulation insulating glue through a plastic encapsulation glue potting process. The conventional welding and / or bonding power pin / terminal process or structure of this existing power module has at least the following technical problems: (1) Due to the complexity of the electrical structure of the power module and the functions and external connection requirements, many power pins are required to work together to realize the different functions of the power module. For example, the control terminal connected to the G / E pole of the power chip, the thermistor terminal connected to the thermistor, the three-phase output terminal, the current input / output terminal, etc. are large in number and arranged closely. As a result, when the power pins are welded / bonded, the power pins are easily affected by the welding / bonding environment, making it difficult for the power pins to be arranged in a straight line. There are cases where the power pins are not aligned with the welding / bonding. As a result, when the power module is applied to the terminal, the power pins cannot be connected to the specified position of the PCB board or the connection is insufficient, resulting in low reliability of the power module and poor terminal application effect. In addition, when the power pins are welded / bonded, there are also cases where the power pins are poorly welded and fall off due to welding voids or virtual pressure, incomplete welding / bonding, and incomplete solder contact, which seriously affects the use of the power module and causes cost losses.

[0004] (2) Based on the process of encapsulating DPIM power modules with resin plastic encapsulation, after the power pins are welded / bonded, silicone gel is poured into the module for encapsulation through a customized mold or equipment. Due to the easy flowability and good adhesion of the colloid, silicone gel is attached to the bottom of the power pins of the encapsulated power module, which seriously affects the subsequent terminal application and the performance of the power module. In addition, the attached silicone needs to be further cleaned, affecting production efficiency.

[0005] (3) Whether the power pin is welded or bonded, the corresponding equipment and materials need to be prepared, and the corresponding equipment and test methods are needed to detect the connection status after the power pin is installed, such as welding void detection, push-pull force test, etc., and after the final potting is completed, the attached silicone needs to be further cleaned. The process is complicated and not conducive to cost control. Other types of packaging modules, such as QFP packaging modules and SMD packaging modules (see CN102790043B), use packaging materials that are different from DPIM. The packaging material used is epoxy resin, but most of the processes are similar, but the above-mentioned technical problems also exist.

[0006] Therefore, the power terminals / pins of the power modules currently on the market are connected to the metal lead frame carrying the power chip by bonding wires or welding leads. There are also cases where the power terminals fall off during epoxy molding due to poor bonding or welding, resulting in power module failure. On the other hand, the close arrangement of the power pins leads to mutual interference of the electromagnetic circuits, and in the pin-bonded wire power modules, the connection needs to use metal connection power pins of different shapes and lengths according to the application scenario, which inevitably increases the length of the electrical circuit to produce greater parasitic inductance and parasitic capacitance, increases power loss during application, and introduces strong electromagnetic interference. During the high-frequency switching process of the power module, voltage overshoots are caused, resulting in transient voltage spikes exceeding the rated value and damaging the power module, and also causing the safe working area of ​​the power module to become narrower, insulation to decrease, and reliability to decrease. Summary of the invention

[0007] In view of this, the purpose of the present invention is to provide a pinless semiconductor integrated power module and terminal equipment, so as to at least solve the problems of increased power loss and introduction of strong electromagnetic interference when the existing power modules with power terminals / pins are used, and transient voltage spikes exceeding the rated value damage the power module, resulting in a narrowing of the safe operating area of ​​the power module, reduced insulation and reduced reliability.

[0008] The present invention solves the above technical problems by the following technical means: A first aspect of the present invention provides a pinless semiconductor integrated power module, comprising: shell; A substrate, the substrate comprising an insulating plate, and a first metal layer and a second metal layer covering two opposite sides of the insulating plate, the shell is packaged on the substrate, the first metal layer faces the shell, the first metal layer is provided with a connecting pad on the outer side of the shell, the connecting pad is used to connect to an external PCB board, and the surface of the connecting pad is covered with a protective layer.

[0009] In combination with the first aspect, in some embodiments, the protective layer is a thin film with a thickness of 1 to 3 microns formed by drying a protective agent solution, and the protective agent solution is an aqueous solution with a protective agent concentration of 85±10%.

[0010] In combination with the first aspect, in some embodiments, the protective agent is at least one of benzotriazole, imidazole organic crystalline base, triazole, and methylbenzotriazole.

[0011] In combination with the first aspect, in some embodiments, the protective layer is prepared as follows: Place the connecting pads on the substrate in anhydrous ethanol, clean them under ultrasonic conditions at a frequency of 15 to 20 kHz for 6 to 8 minutes, then place them in a hot air bake at 60 to 80°C for 4 to 6 minutes, soak the connecting pads in a protective agent solution at 40±2°C for 1 to 1.5 minutes, take them out and place them in pure water, clean them under ultrasonic conditions at a frequency of 25 to 30 kHz for 3 to 6 minutes, then place them in a hot air bake at 100 to 120°C for 10 to 15 minutes, so as to form a protective layer on the connecting pads.

[0012] In combination with the first aspect, in some embodiments, the first metal layer is used to set a circuit arrangement structure, the first metal layer located inside the shell has an electrical gap for the circuit arrangement structure, and a power chip is welded on the first metal layer inside the shell.

[0013] In combination with the first aspect, in some embodiments, the power chip is selected from at least one of a diode, a triode, a MOSFET, an IGBT, a FRD, a SIC and a GAN.

[0014] In combination with the first aspect, in some embodiments, the substrate is any one of a thin film ceramic substrate, a thick film printed ceramic substrate, a direct bonded copper ceramic substrate, an active metal brazed ceramic substrate, a direct electroplated copper ceramic substrate, and a laser activated metal ceramic substrate; The first metal layer and the second metal layer are both copper foil layers.

[0015] A second aspect of the present invention is to provide a terminal device, wherein the terminal device comprises a pinless semiconductor integrated power module as claimed in any one of claims 1 to 7.

[0016] In combination with the second aspect, in some implementations, the terminal device further includes a PCB board, the PCB board has a mounting hole, the housing passes through the mounting hole, and the PCB board is welded to the connecting pad.

[0017] In combination with the second aspect, in some implementations, the terminal device further includes a heat sink, the heat sink is fixedly connected to the PCB board, and the second metal layer faces the heat sink.

[0018] Compared with the prior art, the present invention has the following beneficial effects: (1) The pinless semiconductor integrated power module of the present invention uses the connection pads in the first metal layer on the substrate for electrical internal and external connections, eliminating the layout of pins in various traditional packaging modules. The overall size is compact and can achieve higher power density, which is conducive to the dispersed layout of semiconductor chips on the substrate, reducing heat concentration and improving the power module outflow capacity; (2) The pinless semiconductor integrated power module of the present invention is directly connected to the outside through the connection pad, which reduces the conductive path, improves the reliability of the electrical connection, reduces the risk of poor contact caused by pin size tolerance, welding process deviation, etc., improves the parasitic inductance and capacitance of the pin connection method, optimizes the electromagnetic compatibility of the power module, safe working area and other electrical parameters, and enhances the stability and durability of the module in a high vibration environment; (3) The pinless semiconductor integrated power module of the present invention is partially encapsulated by a housing, and can accurately protect the chip and the wire binding part as needed, avoiding the influence of the packaging material on other parts, and the appearance is flexible and simple; (4) The pinless semiconductor integrated power module of the present invention simplifies the production and assembly process, directly eliminates the processes such as pin bonding / welding, void testing, and push-pull force testing, thereby improving production efficiency. At the same time, the pinless application and local packaging greatly save the material cost of the pins and the housing, further reducing the production and processing costs and improving the economic value of the module; (5) The pinless semiconductor integrated power module of the present invention reduces the process of power pin / terminal welding, optimizes the power module process, and greatly saves R&D equipment / manpower costs; at the same time, the semiconductor integrated power module provided by the present invention completely removes the pins / terminals and directly performs electrical connection through the connecting pads in the first metal layer on the substrate, which greatly reduces the device stray inductance and optimizes the module performance. There is no need to consider the impact caused by whether the power pin / terminal is damaged, and the terminal application has good stability and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a pinless semiconductor integrated power module of the present invention; Figure 2 It is a schematic diagram of the split structure of a pinless semiconductor integrated power module of the present invention; Figure 3 It is a schematic diagram of the connection between the pinless semiconductor integrated power module and the PCB board; Figure 4 It is a schematic diagram of connecting a pinless semiconductor integrated power module with a PCB board and a heat sink; Among them, the power module 100, the housing 120, the substrate 110, the insulating plate 111, the first metal layer 112, the second metal layer 113, the connecting pad 114, the protective layer 115, the power chip 116, the PCB board 200, the mounting hole 210, the heat sink 300, and the bolt 400. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] The terms "first" and "second" in the specification and claims herein are used to distinguish different objects rather than to describe a specific order of objects. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more, for example, multiple processing units refer to two or more processing units, etc., multiple elements refer to two or more elements, etc.

[0022] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0023] The present invention discloses a pinless semiconductor integrated power module, which has no pins and is electrically connected to an external PCB board directly through a connecting pad in a first metal layer on a substrate, thereby solving the problems that the pins or power terminals in the existing power module may fall off due to poor wiring or welding, thereby causing the power module to fail, the power loss may increase during use, strong electromagnetic interference may be introduced, and voltage overshoot may occur during the high-frequency switching process of the power module, resulting in transient voltage spikes exceeding the rated value and damaging the power module, and the safe working area of ​​the power module may become narrower, the insulation may decrease, and the reliability may decrease.

[0024] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0025] Please refer to Figure 1-4 : A pinless semiconductor integrated power module 100 of the present invention comprises a housing 120 and a substrate 110, wherein the substrate 110 comprises an insulating plate 111 and a first metal layer 112 and a second metal layer 113 covering two opposite sides of the insulating plate 111. The housing 120 is packaged on the substrate 110, the first metal layer 112 faces the housing 120, and the first metal layer 112 is provided with a connection pad 114 on the outer side of the housing 120, the connection pad 114 is used to connect to an external PCB board, and the surface of the connection pad 114 is covered with a protective layer 115.

[0026] The housing 120 is made of an electrical insulating material, for example, the electrical insulating material may be hard plastic, silicone gel, epoxy resin, etc., and is used for electrical packaging of the power module 100 to ensure the stability of the internal electrical operation of the power module 100. In particular, when the housing 120 is prepared and molded from epoxy resin material, a metal heat sink may be provided on the non-direct packaging surface of the epoxy resin, and the metal heat sink includes but is not limited to copper sheet, aluminum sheet, etc., to further improve the heat dissipation capacity of the power module 100. When the housing 120 is a hard plastic housing, the packaging method of the power module 100 is to partially package the intermediate circuit, and the packaging morphology is solid-state molded, with a certain mechanical strength to meet the electrical insulation of the module, fixed position and environmental isolation protection, to avoid the impact of the packaging material on other parts.

[0027] The substrate 110 may be a ceramic substrate with electrical transmission and insulation heat dissipation, such as a thin film ceramic substrate (Thin Film Ceramic Substrate, TFC), a thick film printed ceramic substrate (Thick Printing Ceramic Substrate, TPC), a direct bonded copper ceramic substrate (Direct Bonded Copper Ceramic Substrate, DBC), an active metal brazing ceramic substrate (Active Metal Brazing Ceramic Substrate, AMB), a direct electroplated copper ceramic substrate (Direct Plated Copper Ceramic Substrate, DPC) and a laser activated metallization ceramic substrate (Laser Activated Metallization Ceramic Substrate, LAM), etc. The connection pad 114 is provided on the above substrate 110 to achieve connection with an external PCB board. The present invention preferably uses a DBC direct bonded copper ceramic substrate with low cost, good performance and simple manufacturing process. The insulating plate 111 plays the role of insulating support in the substrate 110 , and is made of ceramic materials such as aluminum oxide (Al 2 O 3 ) and aluminum nitride (AlN) with high insulation strength, high thermal conductivity, high temperature resistance and corrosion resistance.

[0028] In order to ensure the effectiveness of the connection between the power module 100 and the external PCB board and the stability of the operation of the power module 100, after the power module 100 is formed, the connection pad 114 of the power module 100 needs to be subjected to surface protection treatment. The surface protection treatment is specifically: forming a uniform protective layer 115 on the bare copper surface of the connection pad 114. The thickness of the protective layer 115 is 1 to 3 microns. The protective layer 115 is a thin film with a thickness of 1 to 3 microns formed by drying the protective agent solution. The protective agent solution is an aqueous solution with a protective agent concentration of 85±10%. The protective agent is at least one of benzotriazole, imidazole organic crystalline base, triazole, and methylbenzotriazole. In the subsequent welding process connected to the external PCB board, when a certain temperature is reached, the organic protective layer 115 is more likely to volatilize.

[0029] The protective layer 115 is formed on the connection pad 114 as follows: Step 11: Place the connection pads 114 on the substrate 110 in anhydrous ethanol and clean them for 6 to 8 minutes under ultrasonic conditions at a frequency of 15 to 20 kHz to clean the impurities generated during the manufacturing process of the connection pads 114 and keep the surface of the connection pads 114 clean. This step is to thoroughly clean the surface of the connection pads 114 of the power semiconductor module to remove impurities such as oil, oxides, and welding waste (generated during chip welding) to ensure that the pad surface has good bonding strength in subsequent processes.

[0030] Step 12: Place the power module 100 cleaned in step 11 in a hot air circulation oven and bake it at 60-80° C. for 4-6 minutes to remove the residual cleaning agent in step 11, ensure that the cleaning agent is completely volatilized and the pad is in a dry state.

[0031] Step 13: Soak the connection pad 114 dried in step 12 in a protective agent solution at 40±2° C. for 1 to 1.5 minutes, take it out and place it in pure water, and clean it under ultrasonic conditions at a frequency of 25 to 30 kHz for 3 to 6 minutes.

[0032] Step 14: Place the power module 100 cleaned in step 13 in a hot air oven at 100-120°C for 10-15 minutes to form a protective layer 115 on the connection pad 114. This step ensures that the power module 100 is dry, that the organic protective layer 115 on the surface of the connection pad 114 is solidified, and that the stability and anti-oxidation performance of the power module 100 are improved.

[0033] The negatively charged benzotriazole ions in the benzotriazole solution can react with the copper atoms on the copper surface of the connection pad 114 to form a protective layer 115 on the copper surface. The protective film formed on the copper surface by the solution of imidazole compounds (imidazole organic crystalline base, triazole, methylbenzotriazole, etc.) is thicker than that of benzotriazole, and the organic film evaporates more slowly during welding, but it can also be used as an optional solvent in the formation process of the protective layer 115. The present invention preferably uses a benzotriazole solution that meets the characteristics of the module, and the protective effect of the protective layer 115 formed on the surface of the connection pad 114 and the effect in the subsequent processing process are the best.

[0034] A protective layer 115 is formed on the surface of the connecting pad 114. On the one hand, it can prevent the part (pad) where the power module 100 is connected to the PCB from being oxidized, and welding voids are generated when the power module 100 is welded to the PCB, thereby affecting the reliability of the power module 100. On the other hand, the protective layer 115 is beneficial to the preservation of the power module 100 after manufacture, and is conducive to mass production and stocking. At the same time, the power module 100 with the protective layer 115 has fewer impurities when connected to the PCB, and the connection with the PCB is more stable, not easy to fall off, and has more reliable performance.

[0035] The first metal layer 112 is used to set the circuit arrangement structure. The first metal layer 112 located in the housing 120 has an electrical gap for the circuit arrangement structure. A power chip 116 is welded on the first metal layer 112 inside the housing 120. In this embodiment, the first metal layer 112 is arranged with four power chips 116 in an H-bridge circuit. The power chip 116 can be a diode, a triode, a MOSFET, an IGBT, an FRD, a SIC, a GAN, etc. The first metal layer 112 serves as a support body. Here, electrical connections between chips and external electrical connections are built according to a certain circuit topology. Common circuit topologies can refer to single tube, three-phase full bridge, H bridge, BUCK, BOOST, chopper circuit, etc. The power chip 116 is welded on the first metal layer 112, and the power chips are electrically connected by ultrasonic bonding of metal wires. The power chip 116 is preferably arranged in the middle local area of ​​the substrate 110.

[0036] The first metal layer 112 is located outside the housing 120 , and a boss connected to the external PCB board, namely, a connecting pad 114 is etched through a half-etching process. The connecting pad 114 includes at least a control pad and a power pad.

[0037] The first metal layer 112 and the second metal layer 113 are both copper foil layers. The thickness of the second metal layer 113 can be selected according to different application requirements, so that the substrate 110 has a heat dissipation function.

[0038] Please refer to Figure 3-4, an embodiment of the present invention also describes a terminal device, which includes the pinless semiconductor integrated power module 100 described in the above embodiment. The terminal device also includes a PCB board 200, the PCB board 200 has a mounting hole 210 matching the housing 120 of the power module 100, the housing 120 passes through the mounting hole 210, and the PCB board 200 is welded to the connecting pad 114. In addition, the terminal device also includes a heat sink 300, the heat sink 300 is fixedly connected to the PCB board 200, and the second metal layer 113 faces the heat sink 300. The assembly process of the power module 100, the PCB board 200 and the heat sink 300 is as follows: The PCB board 200 to be connected is placed horizontally, and the housing 120 is inserted into the mounting hole of the PCB board 200. Solder or soldering pieces are placed at the corresponding positions where the soldering pads of the PCB board 200 are connected to the connecting pads 114 of the power module 100. Then, the boards are placed in a reflow oven and soldered at 140-250°C for 4-6 minutes. During soldering, the heating and cooling sections of the furnace temperature curve need to be set to be controlled below 2°C / second. The downward gravity of the power module 100 itself strengthens the contact degree of the solder / soldering piece welding of the pads during the soldering process. The furnace temperature adjustment below 2°C / second avoids cold solder joints caused by stress and enhances the reliability of terminal applications. The PCB board 200 after welding is turned upside down so that the back of the power module 100 contacts and connects with the external heat sink 300. The PCB board 200 is provided with a clamping screw opening on the outside of the power module 100. The heat sink 300 is provided with a boss or stud that matches the height of the bottom plate of the power module 100. The bolt 400 is passed through the clamping screw opening of the PCB board 200 and is installed and fixed to the heat sink 300. At this point, the assembly of the power module 100, the PCB board 200 and the heat sink 300 is completed.

[0039] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should be included in the scope of the claims of the present invention. The techniques, shapes, and structural parts not described in detail in the present invention are all known technologies.

Claims

1. A pinless semiconductor integrated power module, characterized in that: include: shell; A substrate, the substrate comprising an insulating plate, and a first metal layer and a second metal layer covering two opposite sides of the insulating plate, the shell is packaged on the substrate, the first metal layer faces the shell, the first metal layer is provided with a connecting pad on the outer side of the shell, the connecting pad is used to connect to an external PCB board, and the surface of the connecting pad is covered with a protective layer.

2. The leadless semiconductor integrated power module according to claim 1, characterized in that: The protective layer is a thin film with a thickness of 1 to 3 microns formed by drying a protective agent solution, and the protective agent solution is an aqueous solution with a protective agent concentration of 85±10%.

3. The leadless semiconductor integrated power module according to claim 2, characterized in that: The protective agent is at least one of benzotriazole, imidazole organic crystalline base, triazole, and methylbenzotriazole.

4. The leadless semiconductor integrated power module according to claim 3, characterized in that: The preparation of the protective layer is as follows: Place the connecting pads on the substrate in anhydrous ethanol, clean them under ultrasonic conditions at a frequency of 15 to 20 kHz for 6 to 8 minutes, then place them in a hot air bake at 60 to 80°C for 4 to 6 minutes, soak the connecting pads in a protective agent solution at 40±2°C for 1 to 1.5 minutes, take them out and place them in pure water, clean them under ultrasonic conditions at a frequency of 25 to 30 kHz for 3 to 6 minutes, then place them in a hot air bake at 100 to 120°C for 10 to 15 minutes, so as to form a protective layer on the connecting pads.

5. The leadless semiconductor integrated power module according to claim 1, characterized in that: The first metal layer is used to set up a circuit arrangement structure. The first metal layer located in the shell has an electrical gap for the circuit arrangement structure. A power chip is welded on the first metal layer inside the shell.

6. The leadless semiconductor integrated power module according to claim 5, characterized in that: The power chip is selected from at least one of a diode, a triode, a MOSFET, an IGBT, a FRD, a SIC and a GAN.

7. The leadless semiconductor integrated power module according to claim 1, characterized in that: The substrate is any one of a thin film ceramic substrate, a thick film printed ceramic substrate, a directly bonded copper ceramic substrate, an active metal brazing ceramic substrate, a directly electroplated copper ceramic substrate and a laser activated metal ceramic substrate, and the first metal layer and the second metal layer are both copper foil layers.

8. A terminal device, characterized in that: The terminal device comprises a pinless semiconductor integrated power module as described in any one of claims 1-7.

9. A terminal device according to claim 8, characterized in that: The terminal device further comprises a PCB board, the PCB board has a mounting hole, the housing passes through the mounting hole, and the PCB board is welded to the connecting pad.

10. A terminal device according to claim 9, characterized in that: The terminal device also includes a radiator, which is fixedly connected to the PCB board, and the second metal layer faces the radiator.

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