Electronic module, electronic assembly and electronic device

Abstract

Provided in the present application are an electronic module, an electronic assembly and an electronic device. The electronic module comprises a metal substrate and an electronic component, wherein the electronic component is fixed on the metal substrate. The metal substrate comprises a metal board layer, a porous metal material layer and a connecting metal layer, wherein the porous metal material layer is located between the metal board layer and the connecting metal layer. The porous metal material layer has a plurality of air pores, and the air pores are filled with air, such that the porous metal material layer has a relatively low Young's modulus and a relatively good stress absorption capability. The porous metal material layer is located between the metal board layer and the electronic component, and the orthographic projection, on the metal substrate, of a connected area of the electronic component and the metal substrate at least partially overlaps the area where the porous metal material layer is located. The porous metal material layer can slowly release thermal stress and thermal deformation of the electronic component and the metal substrate caused by thermal expansion mismatch, thereby prolonging the service life of a product.

Description

Electronic module, electronic component and electronic equipment

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on March 27, 2024, with application number 202410371814.X and invention name "An electronic module, electronic component and electronic device", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the technical field of electronic equipment, and in particular to an electronic module, an electronic component and an electronic device. Background Art

[0004] With the development of technology in the field of electronic equipment, the integration of electronic modules in electronic components has gradually increased, and the loss of electronic devices packaged in electronic modules has gradually increased, resulting in a gradual increase in the heat dissipation demand of electronic modules.

[0005] An electronic module usually includes a substrate and electronic devices, and the electronic devices are fixed to the surface of the substrate. In order to improve the heat dissipation effect of electronic devices, a metal substrate can be used as the substrate of the electronic module to carry the electronic devices, and at the same time as a heat dissipation substrate to dissipate heat from the electronic devices. In the prior art, there is a large difference between the thermal expansion coefficient of the metal substrate and the thermal expansion coefficient of the electronic devices. During the thermal deformation process, it is easy to cause the electronic devices and the metal substrate to have different degrees of deformation, and then the electronic devices and the metal substrate are delaminated or the electronic devices peel off. Traditional metal substrates use copper-molybdenum-copper-copper (CPC) composite plates to reduce their thermal expansion coefficients. However, the manufacturing process of the above-mentioned composite plates is complicated and the production cost is high. At the same time, the thermal conductivity of the metal substrate is low (200-300W / mK). Summary of the Invention

[0006] The present application provides an electronic module, an electronic assembly, and an electronic device, which are conducive to absorbing thermal stress, improving the connection strength between electronic components and metal substrates, increasing signal transmission rate, and reducing the cost of electronic modules.

[0007] In the first aspect, the present application provides an electronic module. The electronic module includes a metal substrate and electronic components, and the electronic components are fixed to the metal substrate, and the metal substrate serves as a carrier for carrying the above-mentioned electronic components. Among them, the metal substrate includes a metal plate layer, a porous metal material layer and a connecting metal layer, and the above-mentioned porous metal material layer is located between the metal plate layer and the connecting metal layer. Specifically, the porous metal material layer has a plurality of pores, and the pores are filled with air, so that the porous metal material layer has a lower Young's modulus and can have better stress absorption capacity. The above-mentioned porous metal material layer is located between the metal plate layer and the electronic components, and the connection area between the electronic components and the metal substrate at least partially overlaps with the area where the porous metal material layer is located in the orthographic projection of the metal substrate. The porous metal material layer can relieve the thermal stress and thermal deformation of the metal substrate caused by the thermal expansion mismatch between the electronic components and the metal substrate. This solution can solve the problem of temperature cycle delamination of electronic components on the metal substrate and extend the service life of the product. In addition, the cost of the porous metal material layer is low, and the process of combining the porous metal material layer with the metal plate layer is relatively simple. The cost of the metal substrate is also low, which is conducive to reducing the cost of electronic modules and further reducing the cost of electronic components and electronic equipment.

[0008] The above-mentioned connecting metal layer at least covers the porous metal material layer, and the electronic components are welded or sintered to the connecting metal layer, so that the electronic components are fixed to the metal substrate. On the one hand, the connecting metal layer as a solid structure can improve the connection strength between the electronic components and the metal substrate. On the other hand, the connecting metal layer can also be used to inhibit the oxidation of the porous metal material layer, thereby improving the reliability of the connection between the welded electronic components and the metal substrate, and also improving the connection strength between the electronic components and the metal substrate. In short, by providing a connecting metal layer, the connection reliability between the electronic components and the metal substrate can be improved, which is conducive to improving signal transmission efficiency.

[0009] When configuring the porous metal material layer, the metal substrate can include multiple porous metal material layers, with the connection region between the electronic component and the metal substrate overlapping at least the corner portion of the orthographic projection of the metal substrate with the porous metal material layer. Stress concentration is typically prone to occurring at the corner portion of the connection region. The porous metal material layer can be used to absorb stress at the corner portion of the connection region, thereby improving the reliability of the connection between the electronic component and the metal substrate, providing a stronger connection and enhancing signal transmission efficiency.

[0010] When the porous metal material layer does not completely cover the connection area between the electronic component and the metal substrate, the overlap area between the orthographic projection of the connection area between the electronic component and the metal substrate on the metal substrate and the area where the porous metal material layer is located is at least 50% of the area of ​​the connection area between the electronic component and the metal substrate. This allows stress to be absorbed over more than half of the area of ​​the connection area between the electronic component and the metal substrate. By selecting the location of the porous metal material layer, the electronic component and the metal substrate can be reliably connected while also having good heat dissipation capabilities.

[0011] In a specific technical solution, the thickness of the connecting metal layer is 1um to 100um. When the thickness of the connecting metal layer is within the above range, on the one hand, it can reliably cover the porous metal material layer and provide reliable support for soldering the electronic components to the connecting metal layer. On the other hand, when the thickness of the connecting metal layer does not exceed 100um, the thermal stress mismatch and thermal deformation between the electronic components and the metal substrate can be better transferred to the porous metal material layer without causing delamination between the electronic components and the connecting metal layer.

[0012] Optionally, the connection metal layer has multiple options. For example, the surface of the connection metal layer includes a nickel layer, a silver layer, a gold layer or a palladium layer.

[0013] In a specific technical solution, the porous metal material layer completely covers the surface of the metal plate layer, thereby facilitating simplification of the preparation process of the metal substrate.

[0014] In addition, in other technical solutions, the porous metal material layer may only cover a portion of the surface of the metal plate layer, which is beneficial to reducing the cost of the metal substrate.

[0015] The thickness of the porous metal material layer is 50 μm to 500 μm. On the one hand, a porous metal material layer with a thickness of at least 50 μm can effectively absorb the stress between the electronic components and the metal plate layer, making it less likely for delamination or peeling to occur between the electronic components and the metal plate layer. On the other hand, if the thickness of the porous metal material layer does not exceed 500 μm, the heat generated by the electronic components can be effectively transferred to the metal plate layer, thereby minimizing the impact on heat conduction.

[0016] The thickness of the metal plate layer is 500 to 1000 μm. On the one hand, a metal plate layer at least 500 μm thick can effectively support electronic components and enhance the structural strength of the electronic module. On the other hand, a metal plate layer no thicker than 5000 μm allows heat generated by the electronic components to be effectively transferred to the heat sink through the metal plate layer, thereby improving the thermal conductivity of the metal substrate.

[0017] In a further technical solution, the metal substrate may further include a protective metal layer covering the surface of the metal plate layer facing away from the porous metal material layer. The protective metal layer may include a nickel layer, a silver layer, a gold layer, or a palladium layer. The protective metal layer made of these materials has a strong anti-oxidation capability, preventing oxidation of the metal plate layer and inhibiting the formation of an oxide layer. This improves the reliability of the solder connection and the connection between the heat sink and the metal substrate, providing a strong connection. It also helps improve the thermal conductivity between the metal substrate and the heat sink, thereby enhancing the heat dissipation capacity of the electronic module.

[0018] The electronic module may have various packaging forms. For example, the electronic module includes a packaging shell, which forms a cavity with the metal substrate, and the electronic components are located in the cavity, so that the electronic module forms a cavity packaging structure.

[0019] In one technical solution, the electronic module may include a plastic encapsulating adhesive that encapsulates the electronic components and the metal substrate, so that the electronic module forms a plastic encapsulated structure.

[0020] In a second aspect, the present application provides an electronic assembly. The electronic assembly includes an electronic device and the electronic module provided in the first aspect. The electronic module further includes pins electrically connected to a substrate. The electronic device is electrically connected to electronic components within the electronic module via the pins. The electronic module is less susceptible to delamination and disconnection, improves the connection strength between the electronic components and the metal substrate, increases signal transmission speed, and can also reduce the cost of the electronic module.

[0021] In a third aspect, the present application further provides an electronic device. The electronic device includes a housing and the electronic component provided in the second aspect, wherein the electronic component is disposed within the housing. The electronic component has a high signal transmission rate, which is beneficial for improving the performance of the electronic device and reducing the cost of the electronic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG1 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

[0023] FIG2 is a schematic structural diagram of an electronic component in an embodiment of the present application;

[0024] FIG3 is a schematic structural diagram of an electronic module according to an embodiment of the present application;

[0025] FIG4 is a schematic diagram of a lateral structure of an electronic module in an embodiment of the present application;

[0026] FIG5 is a schematic diagram of a structure of an electronic module connected to a heat sink in an embodiment of the present application;

[0027] FIG6 is a schematic diagram of a partial top view of the electronic module in an embodiment of the present application;

[0028] FIG7 is a schematic structural diagram of an electronic module according to an embodiment of the present application;

[0029] FIG8 is a schematic structural diagram of an electronic module according to an embodiment of the present application;

[0030] FIG9 is a schematic diagram of a partial top view of the electronic module according to an embodiment of the present application;

[0031] FIG10 is a schematic diagram of a partial top view of the electronic module according to an embodiment of the present application;

[0032] FIG11 is a schematic diagram of a partial top view of the electronic module in an embodiment of the present application;

[0033] FIG12 is a schematic structural diagram of an electronic module in an embodiment of the present application.

[0034] Figure numerals: 100-housing; 200-electronic assembly; 210-circuit board; 220-electronic device; 230-electronic module; 1-encapsulation shell; 2-metal substrate; 21-metal plate layer; 22-porous metal material layer; 23-connecting metal layer; 24-protective metal layer; 25-metal block layer; 3-electronic component; 4-pin; 5-lead; 6-passive device; 7-adhesive layer; 8-plastic encapsulation glue; 240-heat sink. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of this application clearer, this application will be further described in detail below with reference to the accompanying drawings.

[0036] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of this application, the singular expressions "a", "an", "above", "the", and "this" are intended to also include expressions such as "one or more", unless the context clearly indicates otherwise.

[0037] References in this specification to "one embodiment" or "a specific embodiment" mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. The terms "including," "comprising," "having," and their variations all mean "including but not limited to," unless otherwise specifically stated.

[0038] To facilitate understanding of the electronic modules, electronic components, and electronic devices provided in the embodiments of the present application, the following first introduces their application scenarios. With technological advancements, the power of electronic modules is increasing. The electronic components within the electronic modules may be semiconductor devices such as chips. During operation, the higher the power, the greater the heat generated by the electronic module. To this end, the substrate within the electronic module is a metal substrate to improve heat dissipation. In practical applications, a radiator can be provided on the side of the electronic module with the metal substrate to dissipate heat from the electronic module and improve the heat dissipation effect of the electronic module.

[0039] In possible embodiments, the electronic device in the embodiments of the present application can be any electronic device that includes an electronic module. For example, the electronic device in the embodiments of the present application can also be an electronic device such as a communication device (such as a router), a computing device (such as a server), a network device (such as a switch) or a storage device (such as a storage array), especially an electronic device with high-power consumption devices.

[0040] FIG1 is a schematic structural diagram of an electronic device in an embodiment of the present application. As shown in FIG1 , in one embodiment, the electronic device may include a housing 100 and an electronic component 200, and the electronic component 200 is disposed in the housing 100. There are multiple options for assembling the electronic component 200 in the housing 100. In a specific embodiment, the electronic component 200 may be housed inside the housing 100, so that the housing 100 can protect the electronic component 200. In another specific embodiment, the electronic component 200 may also be disposed outside the housing 100, depending on the actual product structure design, and this application does not impose any restrictions on this.

[0041] Continuing with Figure 1 , in a specific embodiment, the electronic assembly 200 may be a single board. The electronic assembly 200 includes a circuit board 210, an electronic device 220, and an electronic module 230. The electronic device 220 and the electronic module 230 are both mounted on the circuit board 210 and electrically connected via the circuit board 210 to achieve the functionality of the electronic assembly.

[0042] FIG2 is a schematic diagram of the structure of an electronic assembly in an embodiment of the present application. As shown in FIG2 , the electronic device 220 and the electronic module 230 in the electronic assembly 200 can be electrically connected without using the circuit board 210. In other words, the electronic assembly 200 includes the electronic device 220 and the electronic module 230, and the electronic device 220 and the electronic module 230 are electrically connected via a connecting wire. In short, there are multiple options for connecting the electronic device 220 and the electronic module 230 in the electronic assembly 200, which can be selected and designed according to actual needs.

[0043] The electronic module 230 provided in this application can specifically be a semiconductor RF power amplifier, which is widely used in base stations. Its main function is to amplify the RF signal of the transmission channel so that its output power meets the system requirements, and then transmit the signal through the antenna.

[0044] FIG3 is a schematic structural diagram of an electronic module in an embodiment of the present application. As shown in FIG3 , the electronic module 230 provided in an embodiment of the present application includes a packaging shell 1, a metal substrate 2, and an electronic component 3. The packaging shell 1 and the metal substrate 2 form a cavity, and the electronic component 3 is located in the cavity to form a cavity packaging structure. Specifically, the electronic component 3 is fixed to the metal substrate 2. The metal substrate 2 includes a metal plate layer 21, a porous metal material layer 22, and a connecting metal layer 23. The metal of the porous metal material layer 22 is a porous metal. Specifically, the porous metal material layer 22 has a plurality of pores, such as foamed metal such as foam copper. In addition, the pores in the porous metal material layer 22 are filled with air. That is, the pores are not filled with solid fillers such as solder, which is conducive to maintaining a good stress absorption capacity of the porous metal material layer 22. It can be understood that the metal of the metal plate layer 21 is solid metal. The porous metal material layer 22 is located between the metal plate layer 21 and the electronic component 3. The connecting metal layer 23 at least covers the porous metal material layer 22, and the electronic component 3 is connected to the connecting metal layer 23. Specifically, the electronic component 3 can be connected to the connecting metal layer 23 by welding or sintering.

[0045] The connection area between the electronic component 3 and the metal substrate 2 is located in the area where the porous metal material layer 22 is located. In other words, the metal substrate 2 includes a porous metal material layer 22 at least in the area used to connect the electronic component 3. Since the surface of the porous metal material layer 22 is uneven, it is difficult to fix the electronic component 3 on the surface of the porous metal material layer 22. In the embodiment of the present application, the surface of the porous metal material layer 22 is covered with a connecting metal layer 23, and the connecting metal layer 23 is a solid metal layer, which is conducive to the fixation of the electronic component 3 and the metal substrate 2. In addition, the connecting metal layer 23 can also inhibit the oxidation of the porous metal material layer 22, improve the reliability of the connection between the electronic component 3 and the metal substrate 2, and the connection strength between the electronic component 3 and the metal substrate 2 is good, which is conducive to improving the signal transmission efficiency. The above-mentioned electronic component 3 is specifically a heat-generating component, which is usually a component with high power and large heat generation, such as an active device. The above-mentioned electronic component 3 will generate a lot of heat during operation and conduct the heat to the metal substrate 2 for heat dissipation. In the embodiment of the present application, due to the presence of pores in the porous metal material and the low Young's modulus characteristic, the porous metal material layer 22 can slowly release the thermal stress and thermal deformation caused by the thermal expansion mismatch between the electronic components 3 and the metal substrate 2. Therefore, the electronic module 230 in the embodiment of the present application can solve the problem of thermal stratification of the electronic components 3 on the metal substrate 2, thereby extending the service life of the product. In addition, the cost of the porous metal material layer 22 in the embodiment of the present application is relatively low, and the process of joining the porous metal material layer 22 and the metal plate layer 21 is relatively simple. Therefore, the cost of the metal substrate 2 in the present application is also relatively low, which is conducive to reducing the cost of the electronic module 230, and thereby reducing the cost of electronic components and electronic equipment.

[0046] Furthermore, referring to FIG. 3 , in the embodiment of the present application, the metal substrate 2 is further fixed with pins 4. The electronic components 3 are electrically connected to the pins 4. The ends of the pins 4, distal from the electronic components 3, extend outside the package 1 for connection to electronic components outside the electronic module 230, thereby enabling signal transmission between the electronic module 230 and the outside. In a specific embodiment, the electronic components 3 can be electrically connected to the pins 4 via a wire bonding process, and wires 5 are connected between the electronic components 3 and the pins 4.

[0047] In an optional embodiment, the electronic module 230 in the present application may further include, in addition to the above-mentioned electronic components 3, passive components 6, such as at least one of a resistor, a capacitor and / or an IPD.

[0048] Specifically, the electronic components 3 and passive components in the embodiment of the present application can be soldered to the surface of the metal substrate 2 through a soldering process. Alternatively, the electronic components 3 and passive components 6 can be sintered to the surface of the metal substrate 2 through a sintering process; then, an adhesive layer 7 is formed between the electronic components 3 and the metal substrate 2.

[0049] Specifically, there are many options for the material of the packaging shell 1. For example, the packaging shell 1 can be made of metal, plastic, glass, ceramic or other materials.

[0050] FIG4 is a schematic diagram of a lateral structure of an electronic module according to an embodiment of the present application. As shown in FIG4 , in another embodiment, the electronic module 230 provided herein includes a plastic encapsulant 8, which replaces the encapsulation shell 1 in the above-described embodiment. Specifically, the plastic encapsulant 8 encapsulates the electronic components 3 and the metal substrate 2, forming the electronic module 230 into a plastic-encapsulated structure. The electronic module 230 in this embodiment differs from the electronic module 230 in the embodiment shown in FIG3 only in the different encapsulation method; other features are not described in detail here.

[0051] Figure 5 is a structural schematic diagram of the electronic module connected to the heat sink in an embodiment of the present application. As shown in Figure 5, in one embodiment, the side of the above-mentioned metal substrate 2 facing away from the electronic component 3 is coupled to the heat sink 240, and the heat generated by the electronic component 3 is transferred to the heat sink 240 through the metal substrate 2 and diffused out through the heat sink 240.

[0052] When the metal substrate 2 is specifically provided with the above-mentioned connecting metal layer 23, the surface of the above-mentioned connecting metal layer 23 is a nickel layer, a silver layer, a gold layer or a palladium layer. The above-mentioned metal layers are not easily oxidized and are not easy to generate an oxide layer, which is beneficial to improving the reliability of the welding connection and improving the efficiency of signal transmission. In one embodiment, the above-mentioned connecting metal layer 23 includes at least a two-layer structure, wherein a layer close to the porous metal material layer 22 is a copper layer, and a surface away from the porous metal material layer 22 is a nickel layer, a silver layer, a gold layer or a palladium layer. Since the porous metal material layer 22 needs to be covered, the connecting metal layer 23 needs to have a certain thickness to improve the effect of the connecting metal layer 23 covering the porous metal material layer 22. Therefore, the connecting metal layer 23 is prepared into at least a two-layer structure, which is beneficial to reducing the cost of the connecting metal layer 23 and increasing the thickness of the connecting metal layer 23 to improve the connection reliability.

[0053] Specifically, the thickness of the connecting metal layer 23 can be 1um to 100um. When the thickness of the connecting metal layer 23 is within the above range, on the one hand, the thickness of the connecting metal layer 23 is at least 1um, which can reliably cover the porous metal material layer 22 and provide reliable support for the electronic components 3 to be soldered to the connecting metal layer 23. On the other hand, if the thickness of the connecting metal layer 23 does not exceed 100um, the thermal stress mismatch and thermal deformation between the electronic components 3 and the metal substrate 2 can be better conducted to the porous metal material layer 22, without causing delamination between the electronic components 3 and the connecting metal layer 23. In an optional embodiment, the thickness of the connecting metal layer 23 can be 10um, 15um, 20um, 25um, 30um, 33um, 35um, 40um, 42um or 45um. In addition, in some embodiments, depending on specific product characteristics, the thickness of the connection metal layer 23 may not fall within the above range. For example, the thickness of the connection metal layer 23 may be greater than 100um, and the thickness of the connection metal layer 23 may be 110um, 112um, 120um, 125um, 130um, 135um, 140um, 145um, 150um, or 155um. The thickness of the connection metal layer 23 may also be 50um to 100um. For example, the thickness of the connection metal layer 23 may also be 60um, 65um, 68um, 70um, 72um, 75um, 78um, 80um, 82um, 85um, 90um, 92um, 93um, 95um, 97um, or 99um, etc., which are not listed here one by one.

[0054] In addition, in the embodiment of the present application, the thickness of the porous metal material layer 22 is 50um to 500um. The thickness of the porous metal material layer 22 is within the above range. On the one hand, the thickness of the porous metal material layer 22 is at least 50um, which can better absorb the stress between the electronic components 3 and the metal plate layer 21, so that delamination or peeling is not easy to occur between the electronic components 3 and the metal plate layer 21. On the other hand, if the thickness of the porous metal material layer 22 does not exceed 500um, the heat generated by the electronic components 3 can be better conducted to the metal plate layer 21, and the effect on heat conduction is small. Specifically, the ability of the porous metal material layer 22 to transfer heat is relatively poor relative to the metal plate layer 21. If the thickness of the porous metal material layer 22 does not exceed 500um, it will have little effect on the thermal conductivity of the metal substrate 2. In addition, in some embodiments, depending on the specific product characteristics, the thickness of the porous metal material layer 22 can also be 60um, 65um, 70um, 75um, 80um, 85um, 90um, 92um, 95um, 110um, 118um, 120um, 125um, 130um, 135um, 140um, 145um, 150um or 155um, etc., which are not listed here. In an optional embodiment, the thickness of the connecting metal layer 23 can be 50um to 100um to improve the thermal conductivity of the metal substrate 2 and the heat dissipation capacity of the electronic module 230. For example, the thickness of the metal material layer can be 55um, 60um, 65um, 68um, 70um, 73um, 75um, 77um, 80um, 82um, 85um, 90um, 92um, 94um, 95um, 98um, or 99um, etc.

[0055] In one embodiment, the thickness of the metal plate layer 21 is 500 μm to 5000 μm. Within this range, the metal plate layer 21, being at least 500 μm thick, can effectively support the electronic components 3 and enhance the structural strength of the electronic module 230. Furthermore, if the metal plate layer 21 is no thicker than 5000 μm, the heat generated by the electronic components 3 can be effectively transferred to the heat sink 240 through the metal plate layer 21, thereby improving the thermal conductivity of the metal substrate 2. In an optional embodiment, the thickness of the above-mentioned metal plate layer 21 can be 550um, 600um, 650um, 680um, 700um, 730um, 750um, 770um, 800um, 820um, 850um, 900um, 920um, 940um, 950um, 980um, 990umum, 1000um, 1100um, 1200um, 1500um, 1550um, 1600um, 1700um, 1800um, 2000um, 2100um, 2500um, 2800um, 3000um, 3500um, 3600um, 3800um, 4000um, 4500um, 4600um or 4800um, etc. In addition, in some embodiments, depending on specific product characteristics, the thickness of the metal plate layer 21 may not fall within the above range, that is, the thickness of the metal plate layer 21 may be less than 500 μm. For example, the thickness of the metal plate layer 21 may be 100 μm, 120 μm, 200 μm, 250 μm, 300 μm, 330 μm, 350 μm, 400 μm, 420 μm, or 450 μm, etc., which are not listed here.

[0056] Referring to Figures 3 and 4, the metal substrate 2 in the embodiment of the present application further includes a protective metal layer 24, which covers the surface of the metal plate layer 21 facing away from the porous metal material layer 22. Specifically, the protective metal layer 24 includes a nickel layer, a silver layer, a gold layer, or a palladium layer. The protective metal layer 24 can prevent oxidation of the metal plate layer 21 and is not prone to forming an oxide layer, which is beneficial to improving the reliability of the solder connection and the reliability of the connection between the heat sink 240 and the metal substrate 2. The connection strength is good, and it is beneficial to improve the heat conduction efficiency between the metal substrate 2 and the heat sink 240, thereby improving the heat dissipation capacity of the electronic module 230.

[0057] The porous metal material layer 22 in the present application can cover the entire surface or part of the surface of the metal plate layer 21, as long as it covers the area of ​​the metal substrate 2 where the electronic components 3 are installed. Figure 6 is a partial top view structural schematic diagram of the electronic module in an embodiment of the present application. For ease of understanding, the connecting metal layer 23 is not shown in Figure 6. As shown in Figures 3 to 6, in one embodiment, the porous metal material layer 22 completely covers the surface of the metal plate layer 21, that is, the porous metal material layer 22 covers the entire surface of the metal plate layer 21, and the electronic components 3 can be located at any position of the metal substrate 2. This embodiment is conducive to simplifying the preparation process of the metal substrate 2.

[0058] Figure 7 is a schematic structural diagram of an electronic module in an embodiment of the present application, Figure 8 is a schematic structural diagram of an electronic module in an embodiment of the present application, and Figure 9 is a partial top view schematic structural diagram of an electronic module in an embodiment of the present application. For ease of understanding, the connecting metal layer 23 is not shown in Figure 9. As shown in Figures 7 to 9, in one embodiment, the porous metal material layer 22 covers part of the surface of the metal plate layer 21, and the electronic components 3 are fixed to the area corresponding to the porous metal material layer 22. In this embodiment, the porous metal material layer 22 protrudes from the surface of the metal plate layer 21, and no other metal materials are set in the area of ​​the metal plate layer 21 where the porous metal material layer 22 is not set. Other electronic devices, such as passive devices with low heat generation such as capacitors and inductors, can be directly arranged in the area of ​​the metal plate layer 21 where the porous metal material layer 22 is not set.

[0059] As shown in Figure 9, in an embodiment where the porous metal material layer 22 covers part of the surface of the metal plate layer 21, the area of ​​the porous metal material layer 22 can be made larger than the area of ​​the connection area between the electronic component 3 and the metal substrate 2, and the positive projection of the connection area between the electronic component 3 and the metal substrate 2 on the metal substrate 2 is completely located in the area where the porous metal material layer 22 is located, that is, the porous metal material layer 22 is present at any position below the electronic component 3, so that the porous metal material layer 22 can fully absorb the stress of the electronic component 3.

[0060] FIG10 is a schematic diagram of a partial top view of the structure of the electronic module in an embodiment of the present application, and FIG11 is a schematic diagram of a partial top view of the structure of the electronic module in an embodiment of the present application. For ease of understanding, the connecting metal layer 23 is not shown in FIG10 and FIG11. Referring to FIG10 and FIG11, in some embodiments, a porous metal material layer 22 may be provided below a portion of the structure of the connection area between the electronic component 3 and the metal substrate 2. For example, the metal substrate 2 includes a plurality of porous metal material layers 22, and the connection area between the electronic component 3 and the metal substrate 2 overlaps with the porous metal material layer 22 at least at the corner portion of the orthographic projection of the metal substrate 2. That is, a porous metal material layer 22 is provided below the corner portion of the connection area between the electronic component 3 and the metal substrate 2. Usually, stress concentration is prone to occur at the corner portion of the connection area. The porous metal material layer 22 is used to focus on absorbing the stress of the corner portion of the above-mentioned connection area, thereby improving the reliability of the connection between the electronic component 3 and the metal substrate 2, and having a good connection strength, which is conducive to improving signal transmission efficiency.

[0061] As shown in FIG10 , in an optional embodiment, two porous metal material layers 22 may be included for each electronic component 3, and the two metal material layers are respectively disposed below two side portions opposite to the connection area of ​​the electronic component 3 and the metal substrate 2. As shown in FIG11 , in an optional embodiment, four porous metal material layers 22 may be included for each electronic component 3, and the four metal material layers are respectively disposed below four corner portions opposite to the connection area of ​​the electronic component 3 and the metal substrate 2.

[0062] To enhance the effectiveness of the porous metal material layer 22 in absorbing stress from the electronic component 3, the overlap area between the orthographic projection of the metal substrate 2 and the porous metal material layer 22 at the connection region between the electronic component 3 and the metal substrate 2 can be made at least 50% of the area of ​​the connection region between the electronic component 3 and the metal substrate 2. In this embodiment, stress can be absorbed over more than half of the area of ​​the connection region between the electronic component 3 and the metal substrate 2. By selecting the location of the porous metal material layer 22, the electronic component 3 and the metal substrate 2 can be reliably connected while also having good heat dissipation capabilities.

[0063] FIG12 is a schematic structural diagram of an electronic module in an embodiment of the present application. As shown in FIG12 , when the porous metal material layer 22 covers part of the surface of the metal plate layer 21, a metal block layer 25 can also be provided in the area of ​​the metal plate layer 21 where the porous metal material layer 22 is not provided. The metal block layer 25 is a solid metal layer. In this solution, the porous metal material layer 22 is equivalent to being embedded in the metal block layer 25, and the metal block layer 25 can protect the porous metal material layer 22. In addition, the metal substrate 2 can absorb more heat, which is beneficial to the discharge of heat generated by the electronic components 3. Moreover, the surface of the metal substrate 2 in this embodiment is relatively flat, which is relatively simple and convenient for transportation, storage, and fixing the electronic components 3 on the surface of the metal substrate 2, which is beneficial to simplifying the preparation process of the electronic module 230.

[0064] The following briefly introduces the preparation process of the electronic module 230 provided in this application, which may specifically include the following steps:

[0065] S101, prepare metal plate layer;

[0066] S102, compounding the porous metal material layer onto the surface of the metal plate layer;

[0067] Specifically, a hot pressing process can be used to achieve the composite of the porous metal material layer and the metal plate layer. In one embodiment, the porous metal material layer is a porous copper layer, and the metal plate layer is a copper plate. This means that copper, which is relatively low-cost and has good thermal and electrical conductivity, is used as the primary material for the metal substrate. This reduces the cost of the electronic module and improves its heat dissipation capacity. This, in turn, helps improve the integration and power consumption of the electronic module.

[0068] S103, performing surface treatment on the surface of the porous metal material layer facing away from the metal plate layer to form a metal substrate;

[0069] For example, an electroplating process may be used to plate a connecting metal layer on the surface of the porous metal material layer; or a reduction process may be used to treat the oxide layer on the surface of the metal substrate.

[0070] S104, bonding electronic components in the area where the connecting metal layer covers the porous metal material layer;

[0071] The chip bonding in this step may specifically be a sintering / soldering process, and the bonding material may be sintered silver, sintered copper, or gold-tin solder.

[0072] The preparation process of the packaged electronic module may include the following steps in addition to the above steps:

[0073] Before or after step S104, step S105 is included, fixing the pins to the metal substrate;

[0074] Specifically, the pins are made of metal and can be fixed to the metal substrate via an intermediate structure such as ceramic, LCP or PCB.

[0075] S106, connecting electronic components and pins using a wire bonding process;

[0076] The material of the wire used for wire bonding can be gold, silver, copper or aluminum.

[0077] For solutions that use an encapsulation shell to achieve a cavity packaging structure, the encapsulation shell can then be fixed to the bonding substrate. For solutions that use plastic encapsulation to form a packaging module, the encapsulation can then be encapsulated with the encapsulation glue, and the module units can be cut later. This will not be described in detail here.

[0078] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An electronic module, characterized in that: It comprises a metal substrate and electronic components, wherein the electronic components are fixed to the metal substrate; The metal substrate comprises a metal plate layer, a porous metal material layer, and a connecting metal layer, wherein the porous metal material layer has a plurality of pores filled with air; the porous metal material layer is located between the metal plate layer and the electronic component, and the connection area between the electronic component and the metal substrate at least partially overlaps with the area where the porous metal material layer is located in the orthographic projection of the metal substrate; The connection metal layer at least covers the porous metal material layer, and the electronic components are welded or sintered to the connection metal layer.

2. The electronic module according to claim 1, wherein The metal substrate includes a plurality of porous metal material layers, and the connection area between the electronic component and the metal substrate overlaps with the porous metal material layer at least at a corner portion of the orthographic projection of the metal substrate.

3. The electronic module according to claim 1 or 2, characterized in that: The overlapping area of ​​the connection region between the electronic component and the metal substrate on the orthographic projection of the metal substrate and the region where the porous metal material layer is located is at least 50% of the area of ​​the connection region between the electronic component and the metal substrate.

4. The electronic module according to any one of claims 1 to 3, characterized in that: The thickness of the connecting metal layer is 1um to 100um.

5. The electronic module according to any one of claims 1 to 4, characterized in that: The surface of the connecting metal layer includes a nickel layer, a silver layer, a gold layer or a palladium layer.

6. The electronic module according to any one of claims 1 to 5, characterized in that: The porous metal material layer completely covers the surface of the metal plate layer.

7. The electronic module according to any one of claims 1 to 5, characterized in that: The porous metal material layer covers a portion of the surface of the metal plate layer.

8. The electronic module according to any one of claims 1 to 7, wherein: The thickness of the porous metal material layer is 50um to 500um.

9. The electronic module according to any one of claims 1 to 8, characterized in that: The thickness of the metal plate layer is 500um to 1000um.

10. The electronic module according to any one of claims 1 to 9, characterized in that: The metal substrate further includes a protective metal layer, which covers the surface of the metal plate layer facing away from the porous metal material layer. The protective metal layer includes a nickel layer, a silver layer, a gold layer or a palladium layer.

11. The electronic module according to any one of claims 1 to 10, characterized in that: The electronic module includes a packaging shell, wherein the packaging shell and the metal substrate form a cavity, and the electronic components are located in the cavity.

12. The electronic module according to any one of claims 1 to 10, characterized in that: The electronic module includes a plastic sealant, and the plastic sealant seals the electronic components and the metal substrate.

13. An electronic component, characterized in that: The electronic device comprises an electronic module according to any one of claims 1 to 12 and an electronic component, wherein the electronic module further comprises pins electrically connected to the electronic components; and the electronic device is electrically connected to the electronic components in the electronic module via the pins.

14. An electronic device, characterized in that: The electronic device comprises a housing and the electronic component according to claim 13, wherein the electronic component is arranged in the housing.

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