Packaging structure and preparation method thereof, packaging module and electronic device

Abstract

The present application provides a packaging structure, which includes a conductive substrate, a packaging layer located on the surface of the conductive substrate, electronic components located in the packaging layer, and a circuit layer located on the surface of the conductive substrate, wherein the circuit layer is electrically connected to the conductive substrate and the electronic components, respectively, and the resistance of the conductive substrate and / or the circuit layer increases with the increase of current or temperature. The present application also provides a packaging module using the packaging structure, an electronic device using the packaging module, and a method for preparing the packaging structure. By increasing the resistance of different structures in the packaging structure with the increase of current or temperature, the impedance can be increased to reduce the current when overcurrent (overtemperature) occurs, thereby preventing the burning of electronic components, thereby achieving the purpose of self-protection from overcurrent or overtemperature.

Description

Technical Field

[0001] The present application relates to a packaging structure capable of realizing over-current or over-temperature self-protection, a method for preparing the packaging structure, a packaging module using the packaging structure, and an electronic device using the packaging module. Background Art

[0002] A power semiconductor device is a package structure formed by packaging a chip. A power semiconductor device is usually electrically connected to a printed circuit board (PCB) through surface mount technology (SMT).

[0003] However, once overcurrent occurs in power semiconductor devices, especially power supply type power semiconductor devices, the internal packaged chips may burn out. After the chips burn out, it is very difficult to repair the highly packaged structure. Moreover, the heat from the burning chips will also destroy the packaging polymer, causing the burned surface to further extend to the PCB mainboard, eventually causing the PCB mainboard to burn out and become scrapped. Summary of the invention

[0004] A first aspect of an embodiment of the present application provides a packaging structure, which includes a conductive substrate, a packaging layer located on the surface of the conductive substrate, electronic components located in the packaging layer, and a circuit layer located on the surface of the conductive substrate, wherein the circuit layer is electrically connected to the conductive substrate and the electronic components, respectively, and the resistance of the conductive substrate and / or the circuit layer increases with the increase of current or temperature.

[0005] The packaging structure introduces a structure in which resistance increases with the increase of current or temperature, so that the packaging structure can increase the impedance of the circuit when the circuit is overcurrent or overtemperature, thereby reducing the current flowing through the electronic components and reducing the risk of electronic components being burned, thereby achieving the purpose of overcurrent or overtemperature self-protection; and structures with overcurrent self-protection function can be set at different parts of the packaging structure according to actual needs, thereby improving the structural design flexibility of the packaging structure.

[0006] In some embodiments, the material of the conductive substrate and / or the circuit layer includes a positive temperature coefficient (PTC) material.

[0007] By introducing PTC materials into the conductive substrate and / or circuit layer in the packaging structure, the conductive substrate and the circuit layer can have the characteristic that their own resistance increases with the increase of circuit current or temperature, so that the packaging structure has the function of self-protection against overcurrent or overtemperature, reducing the risk of burning electronic components and the entire packaging structure, thereby improving the performance stability and yield of the packaging structure.

[0008] In some embodiments, the circuit layer includes a first layer disposed close to the electronic components and a second layer disposed on a surface of the first layer away from the electronic components, and the resistance of the first layer and / or the second layer increases with increasing current or temperature.

[0009] The circuit layer adopts a multi-layer structural design, and according to actual needs, any one or two layers can have the characteristic that the resistance can increase with the increase of current or temperature. While ensuring the purpose of over-current or over-temperature self-protection, the structural design flexibility of the circuit layer is improved and the cost is reduced.

[0010] In some embodiments, the packaging structure includes a first area and a second area connected to the first area, the electronic components are located in the first area, the second area is located at the outer edge of the first area away from the electronic components, and the resistance of the conductive substrate and / or the circuit layer in the first area increases with the increase of current or temperature.

[0011] Part of the packaging structure, especially in the area close to the electronic components, is designed to have a structure whose resistance increases with the increase of current or temperature. When the current flowing through the electronic components is too large or the temperature around the electronic components is too high, the structure with over-current self-protection function located in this area can quickly sense the change in current or temperature and respond quickly, thereby achieving the purpose of over-current or over-temperature self-protection. In addition, only the local structure of the packaging module has the over-current self-protection function, which can effectively reduce costs and does not affect the electrical performance of other areas.

[0012] In some embodiments, the conductive substrate includes an insulating layer and a conductive layer located on a surface of the insulating layer, and the resistance of the conductive layer increases with increasing current or temperature.

[0013] The conductive substrate adopts a multi-layer structure design, which can effectively reduce the thickness of the conductive layer while meeting the purpose of circuit overcurrent or overtemperature self-protection, thereby reducing costs. Especially for thicker electronic components, the thickness of the conductive substrate needs to be designed to be thicker. By designing the conductive substrate into a structure with an insulating layer and a conductive layer stacked, the thickness of the conductive layer can be reduced, effectively reducing costs. At the same time, due to the thinning of the thickness of the conductive layer in the conductive substrate, the resistance of the conductive substrate when the circuit is working normally can also be reduced, and the conductivity of the conductive substrate when the circuit is working normally can be improved.

[0014] In some embodiments, the packaging structure also includes a first conductive part and a second conductive part, the first conductive part and the second conductive part are both located in the packaging layer, the first conductive part electrically connects the circuit layer and the electronic components, the second conductive part electrically connects the circuit layer and the conductive substrate, and the resistance of the first conductive part and / or the second conductive part increases with the increase of current or temperature.

[0015] By further designing the first conductive part and / or the second conductive part to have the function of over-current or over-temperature self-protection, the molding is simple and the cost is low. In particular, the first conductive part is directly connected to the electronic component, which can directly sense the temperature of the electronic component and whether the current flowing through the electronic component is too large, thereby responding quickly, reducing the risk of burning the electronic component and improving the yield of the packaging structure.

[0016] In some embodiments, the packaging structure further includes a plurality of connection pads disposed on the circuit layer away from the surface of the electronic component, and the resistance of at least one of the connection pads increases with an increase in current or temperature.

[0017] By further designing the connection pad connecting the packaging structure and the circuit board to have an over-current or over-temperature self-protection function, the over-current self-protection function of the packaging structure can be enhanced. In particular, the connection pad connected to the power input terminal of the circuit board is designed to have an over-current or over-temperature self-protection function. The connection pad can quickly sense whether the input current is too large and respond quickly to provide an over-current or over-temperature self-protection effect; and the structural design flexibility of the packaging structure can be improved.

[0018] In some embodiments, an opening is provided on the conductive substrate, and the electronic component is located in the opening.

[0019] By setting openings on the conductive substrate and burying the electronic components in the conductive substrate, the total thickness of the packaging structure can be effectively reduced, the density of the embedded electronic components can be increased, and the development needs of the packaging structure being multifunctional, thin and short can be met.

[0020] A second aspect of an embodiment of the present application provides a packaging module, which includes a packaging structure, a circuit board, and a plurality of connecting parts, wherein the plurality of connecting parts electrically connect the packaging structure and the circuit board, and the packaging structure is the packaging structure as described above.

[0021] By electrically connecting a packaging structure with an overcurrent self-protection function to a circuit board, the risk of the circuit board being burned due to overcurrent or overtemperature can be reduced, thereby improving the yield and service life of the packaging module.

[0022] In some embodiments, the resistance of the connection portion increases with increasing current or temperature.

[0023] By further designing the connection part connecting the packaging structure and the circuit board to have an over-current or over-temperature self-protection function, the over-current self-protection function of the packaging module can be enhanced. In particular, the connection part connected to the power input terminal of the circuit board is designed to have an over-current or over-temperature self-protection function. The connection part can quickly sense whether the input current is too large and respond quickly to provide an over-current or over-temperature self-protection effect.

[0024] A third aspect of an embodiment of the present application provides a packaging module, which includes a packaging structure, a circuit board, and a plurality of connecting parts. The packaging structure includes a conductive substrate, a packaging layer located on the surface of the conductive substrate, electronic components located in the packaging layer, and a circuit layer located on the surface of the conductive substrate. The plurality of connecting parts electrically connect the packaging structure and the circuit board, and the resistance of at least one of the connecting parts increases with the increase of current or temperature.

[0025] The packaging structure is electrically connected to the circuit board through the connecting part. By designing the connecting part to have over-current or over-temperature self-protection function, it can respond to the larger current of the power input as quickly as possible, and improve the reaction speed of the connection part resistance to current or temperature, thereby more effectively achieving the purpose of over-current or over-temperature self-protection.

[0026] A fourth aspect of an embodiment of the present application provides an electronic device, which includes the packaging module as described above.

[0027] By applying the above-mentioned packaging module to an electronic device, the packaging module has the function of self-protection against overcurrent or overtemperature, which can reduce the risk of the packaging module being burned due to overcurrent or overtemperature, thereby improving the performance stability of the electronic device, and further improving the yield and life of the electronic device.

[0028] A fifth aspect of an embodiment of the present application provides a method for preparing a packaging structure, the preparation method comprising: forming a packaging layer on the surface of a conductive substrate, wherein electronic components are encapsulated in the packaging layer; and forming a circuit layer on the surface of the conductive substrate, wherein the circuit layer is electrically connected to the conductive substrate and the electronic components, respectively, and the resistance of the conductive substrate and / or the circuit layer increases with the increase of current or temperature, thereby obtaining the packaging structure.

[0029] According to actual needs, the structures of different parts of the packaging structure are designed to have the function of over-current or over-temperature self-protection, which improves the structural design flexibility of the packaging structure. The manufacturing of the packaging structure does not require special molding equipment and special processes. The preparation method is simple, easy to implement, low cost, and easy to mass produce.

[0030] In some embodiments, the conductive substrate and / or the circuit layer are made of a PTC material.

[0031] By changing the structural materials at different parts of the packaging structure, the corresponding structure is provided with an over-current or over-temperature self-protection function, which is easy to implement and has a simple molding method.

[0032] In some embodiments, the circuit layer includes a first layer and a second layer, and the resistance of the first layer and / or the second layer increases with the increase of current or temperature. The method for preparing the circuit layer includes the steps of: forming the first layer on the surface of the conductive substrate, and the resistance of the first layer increases with the increase of current or temperature; arranging metal on the surface of the first layer to form the second layer; and patterning the first layer and the second layer to form the circuit layer. Or, the method for preparing the circuit layer includes the steps of: arranging metal on the surface of the conductive substrate to form the first layer; forming the second layer on the surface of the first layer, and the resistance of the second layer increases with the increase of current or temperature; and patterning the first layer and the second layer to form the circuit layer.

[0033] Making circuit layers in layers can reduce the thickness of the layer with over-current or over-temperature self-protection function, and can also reduce the thickness of the metal material layer, thereby effectively reducing the molding difficulty and manufacturing cost.

[0034] In some embodiments, the packaging structure includes a first area and a second area connected to the first area, the electronic components are located in the first area, the second area is located at the outer edge of the first area away from the electronic components, the conductive substrate includes a third conductive portion corresponding to the first area, and the resistance of the third conductive portion increases with the increase of current or temperature. The preparation method of the conductive substrate includes the steps of: forming a window through a metal plate; laminating a carrier film on the metal plate; setting a third conductive portion in the window, and the resistance of the third conductive portion increases with the increase of current or temperature; and removing the carrier film to obtain the conductive substrate.

[0035] By setting the conductive substrate in the area close to the electronic components to have the function of over-current or over-temperature self-protection, the area of ​​the third conductive part can be reduced and the cost can be effectively reduced; moreover, the molding method of the conductive substrate is simple and easy to implement; in addition, only the third conductive part has the function of over-current or over-temperature self-protection, which will not affect the molding method and electrical performance of the conductive substrate in other areas.

[0036] In some embodiments, the packaging structure includes a first area and a second area connected to the first area, the electronic components are located in the first area, the second area is located at the outer edge of the first area away from the electronic components, and the resistance of the circuit layer in the first area increases with the increase of current or temperature.

[0037] The circuit layer is designed to have an over-current or over-temperature self-protection function in an area close to electronic components, which can effectively reduce costs without affecting the manufacturing and electrical performance of circuit layers in other areas.

[0038] In some embodiments, the conductive substrate includes an insulating layer and a conductive layer disposed on at least one surface of the insulating layer, and the resistance of the conductive layer increases with an increase in current or temperature.

[0039] A conductive layer with over-current or over-temperature self-protection function is formed on the surface of the insulating layer. The molding method is simple and has low requirements on molding equipment. It can be achieved without changing traditional molding equipment and has low cost.

[0040] In some embodiments, the preparation method also includes the steps of: setting a first conductive part and a second conductive part in the packaging layer, the first conductive part electrically connecting the circuit layer and the electronic component, the second conductive part electrically connecting the circuit layer and the conductive substrate, and the resistance of the first conductive part and / or the second conductive part increases with the increase of current or temperature.

[0041] The circuit layer is electrically connected to the electronic components and the conductive substrate through the first conductive part and the second conductive part respectively, without the need for special molding equipment and special processes. The preparation method is simple, easy to implement and low in cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of the structure of a packaging module according to an embodiment of the present application.

[0043] Figure 2 It is a structural schematic diagram of a packaging structure of an embodiment of the present application.

[0044] Figure 3 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0045] Figure 4 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0046] Figure 5 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0047] Figure 6 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0048] Figure 7 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0049] Figure 8 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0050] Fig. 9 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0051] Fig.10It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0052] Fig.11 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0053] Fig.12 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0054] Fig.13 It is a structural schematic diagram of a packaging structure of another embodiment of the present application.

[0055] Fig.14 It is a structural schematic diagram of a packaging module according to another embodiment of the present application.

[0056] Fig.15 It is a schematic structural diagram of a conductive substrate according to an embodiment of the present application.

[0057] Fig.16 This is an embodiment of the present application. Fig.15 A schematic structural diagram of an opening formed on a conductive substrate is provided.

[0058] Fig.17 This is an embodiment of the present application. Fig.16 A schematic structural diagram of a surface-bonded carrier film of a conductive substrate is provided.

[0059] Fig.18 This is an embodiment of the present application. Fig.17 A schematic diagram of the structure in which electronic components are arranged in a receiving cavity is provided.

[0060] Fig.19 This is an embodiment of the present application. Fig.18 A schematic structural diagram of a first plastic sealing part filled in a receiving cavity for electronic components.

[0061] Fig. 20 This is an embodiment of the present application. Fig.19 Schematic diagram of the structure after removing the carrier film.

[0062] Fig.21 This is an embodiment of the present application. Fig. 20 A schematic structural diagram of a second plastic sealing portion formed on two surfaces of a provided conductive substrate.

[0063] Fig. 22 This is an embodiment of the present application. Fig.21 A schematic structural diagram of a second plastic encapsulation portion provided to form a through hole and thus form an encapsulation layer.

[0064] Fig.23 is Fig. 22 A schematic structural diagram of forming a conductive portion in a through hole and forming a copper layer on the surface of a packaging layer is provided.

[0065] Fig.24 It is patterned Fig.23 A schematic diagram of the structure of a circuit layer formed by providing a conductive layer.

[0066] Fig.25 and Fig.26 is Fig.24 A schematic diagram of the structure of increasing the surface of a circuit layer to form a dielectric layer and another copper layer is provided.

[0067] Fig. 27 Another embodiment of the present application is Fig. 22 A schematic structural diagram of forming a conductive portion in a through hole and forming a PPTC material layer on the surface of a packaging layer is provided.

[0068] Fig.28 It is patterned Fig. 27 A schematic diagram of the structure of a circuit layer formed by providing a PPTC material layer.

[0069] Fig.29 and Fig.30 is Fig.28 A schematic diagram of the structure of adding layers to the surface of a circuit layer to form a dielectric layer and another PPTC material layer is provided.

[0070] Fig.31 Another embodiment of the present application is Fig. 22 A schematic structural diagram of forming a conductive portion in a through hole, forming a copper layer on the surface of a packaging layer, and forming a PPTC material layer on the surface of the copper layer is provided.

[0071] Fig.32 It is patterned Fig.31 A schematic diagram of the structure of a circuit layer formed by providing a copper layer and a PPTC material layer.

[0072] Fig.33 and Fig.34 is Fig.32 A schematic diagram of the structure of adding layers on the surface of a circuit layer to form a dielectric layer, another copper layer and another PPTC material layer is provided.

[0073] Fig.35 It is a schematic structural diagram of a conductive substrate provided in another embodiment of the present application.

[0074] Fig.36 is Fig.35 A schematic structural diagram of a filling port formed on a conductive substrate is provided.

[0075] Fig.37 is Fig.36 A schematic structural diagram of a carrier film bonded to a conductive substrate having a filling port is provided.

[0076] Fig.38is Fig.37 A schematic structural diagram of a third conductive portion formed by filling a filling port of a conductive substrate with PPTC material.

[0077] Fig.39 is Fig.38 A structural schematic diagram of an opening being provided on the third conductive portion.

[0078] Main component symbols

[0079] Packaging module 1000, 2000

[0080] Package structure 100', 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h, 100i, 100j, 100k, 100l

[0081] Conductive substrate 1', 1, 1a, 1b, 1i, 1k

[0082] Insulation layer 11

[0083] Conductive layer 12

[0084] Encapsulation layer 13

[0085] Opening 2',2

[0086] Electronic components 3',3

[0087] Encapsulation layer 4',4

[0088] The first plastic sealing part 41

[0089] The second plastic sealing part 42

[0090] The third plastic sealing part 43

[0091] Through hole 44

[0092] Circuit layer 5',5,5c,5e,5f,5j

[0093] First layer 51e, 51f

[0094] Second layer 52e, 52f

[0095] First Line 51j

[0096] Second line 52j

[0097] First conductive portion 61 ′, 61, 61c

[0098] Second conductive parts 62 ′, 62 , 62 c

[0099] Metal Plate 7

[0100] Surface treatment layer 8

[0101] Carrier film 20

[0102] Accommodating chamber 30

[0103] Copper layer 40,50

[0104] PPTC material layer 40c, 60

[0105] The third conductive portion 9

[0106] Window 70

[0107] Zone 1A

[0108] Zone 2B

[0109] Circuit board 200

[0110] Connecting part 300, 3001 DETAILED DESCRIPTION

[0111] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0112] like Figure 1As shown, a packaging module 1000 is shown. The packaging module 1000 includes a packaging structure 100' and a circuit board 200, and the packaging structure 100' is electrically connected to the circuit board 200 through a plurality of connecting parts 300. Among them, the packaging structure 100' can be a power semiconductor device for power processing, including frequency conversion, voltage conversion, current conversion, power management, etc. The packaging module 1000 is applied to an electronic device (not shown), and the electronic device can be an electric energy conversion device, and the electric energy conversion device can be mounted on an electric energy conversion device to complete various power functions of the device. For example, the electronic device in this embodiment can be applied in the field of electric vehicle power systems, wherein the electronic device can be a motor controller, and the packaging structure 100' can be a power conversion unit assembled in the motor controller; the electronic device can also be an on-board charger (OBC), and the packaging structure 100' is an energy conversion unit in the OBC; the electronic device can also be a low-voltage control power supply, and the packaging structure 100' is a DC-DC conversion unit in the low-voltage control power supply, etc. It is understandable that in other embodiments, the electronic device is not limited to the field of electric vehicles, but can also be widely used in traditional industrial control, communication, smart grid, electrical appliances and other fields, for example, it can be applied to uninterruptible power supply (UPS) of data centers, inverters of photovoltaic power generation equipment, power supplies of servers, switching power supplies of electrical appliances (such as refrigerators), etc. It is also understandable that in other embodiments, the electronic device is not limited to an electric energy conversion device, and the packaging structure 100' is not limited to electric energy conversion, but can also be used in electronic devices to change voltage, frequency, etc. to achieve circuit control functions.

[0113] like Figure 2 As shown, a packaging structure 100' is provided in one embodiment, the packaging structure 100' comprises a conductive substrate 1', an opening 2' formed on the conductive substrate 1', an electronic component 3' accommodated in the opening 2', a packaging layer 4' arranged on the surface of the conductive substrate 1', a circuit layer 5' arranged on the surface of the conductive substrate 1', a first conductive portion 61' buried in the packaging layer 4' and a second conductive portion 62' buried in the packaging layer 4', the packaging layer 4' also encapsulates the electronic component 3', the first conductive portion 61' electrically connects the circuit layer 5' and the electronic component 3', and the second conductive portion 62' electrically connects the circuit layer 5' and the conductive substrate 1'.

[0114] It can be understood that the number of layers of the circuit layer 5' can be designed according to actual needs, and it can be a single-layer circuit or a multi-layer circuit. In this embodiment, the circuit layer 5' has four layers, which are respectively arranged on two opposite surfaces of the conductive substrate 1', that is, two layers of the circuit layer 5' are arranged on the same side of the conductive substrate 1', one of which is buried in the packaging layer 4' to form an inner layer circuit, and the other is located on the surface of the packaging layer 4' to form an outer layer circuit.

[0115] Combination Figure 1 and Figure 2 The packaging structure 100' is electrically connected to the circuit board 200 through a plurality of connecting parts 300. In the present embodiment, the conductive substrate 1' is a copper substrate, the circuit layer 5' may be made of copper, and the connecting part 300 may be made of conductive paste. In actual use, when the current or temperature exceeds a certain range, the electronic components 3' inside the packaging structure 100' may be burned due to overcurrent or overtemperature. After the electronic components 3' are burned, maintenance is very difficult due to the high degree of packaging of the packaging structure 100'. Moreover, the heat from the burning of the electronic components 3' will also damage the packaging layer 4', causing the burned surface to extend further, and eventually causing the entire circuit board 200' to be burned and scrapped.

[0116] See also Figure 3 In order to solve the above-mentioned problem of the packaging structure 100', this embodiment provides a packaging structure 100a. The packaging structure 100a includes a conductive substrate 1a, an opening 2 formed on the conductive substrate 1a, an electronic component 3 accommodated in the opening 2, a packaging layer 4 provided on the surface of the conductive substrate 1a, and a circuit layer 5 provided on the surface of the conductive substrate 1a, wherein the packaging layer 4 encapsulates the electronic component 3, and the resistance of the conductive substrate 1a increases with the increase of current or temperature.

[0117] Specifically, the material of the conductive substrate 1a includes a positive temperature coefficient (PTC) material. PTC material is a material whose resistance value changes with temperature in a positive temperature coefficient. At normal temperature, the PTC material exhibits a lower resistance value so that the circuit connected to it can operate normally. However, when an overcurrent or overtemperature occurs in the circuit, the Joule heat generated by the overcurrent causes the PTC material to reach a high temperature state, or the excessively high ambient temperature around the PTC material causes it to reach a high temperature state. The resistance of the PTC material increases abnormally, thereby limiting the flow of circuit current, thereby having the function of protecting the circuit. The protection of the circuit by the PTC material is based on a high-resistance current limiting mechanism, which does not completely cut off the circuit. There is still a small leakage current passing through the circuit. When the current becomes smaller or the temperature drops, the temperature of the PTC material drops, and the resistance value can gradually return to the initial state, so it has recoverability. Based on the excellent resistance change characteristics of PTC materials, the present application uses PTC materials to prepare the conductive substrate 1a of the packaging structure 100a. When the packaging structure 100a has overcurrent or overtemperature, the resistance of the conductive substrate 1a made of PTC material increases, limiting the circuit current. When the current decreases or the temperature drops, the resistance of the conductive substrate 1a returns to its initial state, thereby providing self-protection for the circuit from overcurrent or overtemperature. The conductive substrate 1a will not affect the circuit performance during normal operation, and can effectively reduce the risk of burning the electronic components 3 in the event of overcurrent or overtemperature, thereby improving the performance stability, yield and service life of the packaging structure 100a. Moreover, combined with Figure 2 As shown, the conductive substrate 1a is directly made of PTC material. Compared with the original conductive substrate 1', the thickness of the conductive substrate 1a will not increase, which is beneficial to the slimming and miniaturization of the packaging structure 100a. In addition, when the electronic components 3 are embedded in the packaging structure 100a, the thickness of the conductive substrate 1a usually needs to exceed the thickness of the electronic components 3. Therefore, especially for thinner electronic components 3, since the thickness of the conductive substrate 1a is thin, the conductive substrate 1a is made of PTC material as a whole, which can enhance the over-current or over-temperature self-protection effect. At the same time, the structure of the conductive substrate 1a is simpler and easy to shape.

[0118] Specifically, the PTC material in this embodiment is a polymer-based positive temperature coefficient (PPTC) material, which includes a polymer and a conductive filler. The PPTC material is made by adding a conductive filler to the polymer. Due to the presence of the conductive filler, the PPTC material has conductivity under low current or low temperature conditions. When a certain current or temperature is exceeded, the polymer expands, and the impedance of the PPTC material increases, which serves the purpose of overcurrent or overtemperature self-protection. The conductive substrate 1a is formed using PPTC material, and the forming is simple, without the need for special processes and special forming equipment. In addition, the polymer-based conductive substrate 1a has better interface compatibility with the encapsulation layer 4 and is not easy to delaminate.

[0119] The polymer may be a polyolefin, specifically a crystalline polyolefin, such as at least one of polyethylene (PE), low-density polyethylene (LDPE), high-density polyethylene (HDPE), ethylene tetrafluoroethylene copolymer (ETFE), polytetrafluoroethylene (PTFE), and polyvinylidene fluoride (PVDF). The conductive substrate 1a prepared by using crystalline polyolefin has the performance of high-temperature expansion and low-temperature recovery, and can also ensure that the substrate has excellent mechanical properties.

[0120] The conductive filler includes at least one of conductive carbon black, metal powder and conductive ceramic. The conductive carbon black, metal powder and conductive ceramic are all conductive fillers with excellent conductive properties, which can improve the conductivity of PPTC materials under low current or low temperature conditions. The metal powder can be titanium powder, nickel powder, copper powder, etc. The conductive ceramic can be a fast ion conductor ceramic powder, such as halogen and chalcogen compounds of silver and copper, or β-Al 2 O 3 High mobility monovalent cation oxides with a structure or calcium fluoride (CaF 2 ) structure with high concentration defects (such as CaO·ZrO 2 , Y 2 O 3 ·ZrO 2 ) etc. Fast ion conductor ceramic materials have good fast ion conductor charging and discharging characteristics and are highly sensitive to temperature and current. Therefore, the reaction speed of the conductive substrate 1a made of PPTC materials to overcurrent or overtemperature can be improved, thereby improving the effect of overcurrent or overtemperature self-protection.

[0121] It can be understood that the conductive filler exists in the polymer in a granular form and is evenly dispersed in the polymer to ensure that the conductive substrate 1a has excellent electrical properties. In this embodiment, the particle shape of the conductive filler can be spherical. In other embodiments, the particle shape of the conductive filler can also be an elongated strip or other irregular shape with a certain aspect ratio. The amount of the conductive filler added can be set according to the type of the actual packaged electronic component 3 or other actual use requirements (such as the maximum current of the circuit). It is usually used in power semiconductor devices, and the amount of the conductive filler added is in the range of 5wt%-80wt%.

[0122] like Figure 3 As shown, the opening 2 is formed by lamination, exposure, development and etching. Since the conductive substrate 1a is made of PPTC material as a whole, the opening 2 is formed by etching, which is simple, easy to implement and low in cost. In other embodiments, the opening 2 can also be formed by laser drilling or mechanical drilling.

[0123] The electronic component 3 may include one or more active devices, such as active chips, including but not limited to power chips, digital chips, radio frequency chips, etc. The electronic component 3 is embedded in the conductive substrate 1 a, and the packaging layer 4 completely covers the electronic component 3 .

[0124] like Figure 3 As shown, in this embodiment, the circuit layer 5 has four layers, which are respectively arranged on two opposite surfaces of the conductive substrate 1a, that is, two layers of the circuit layer 5 are arranged on the same side of the conductive substrate 1a, one of which is buried in the packaging layer 4 to form an inner layer circuit, and the other is located on the surface of the packaging layer 4 to form an outer layer circuit. It can be understood that the number of layers of the circuit layer 5 can be designed according to actual needs, and the circuit layer 5 can also be a single layer, or other more than four layers.

[0125] like Figure 3 As shown, the encapsulation layer 4 includes a first plastic encapsulation part 41 accommodated in the opening 2, a second plastic encapsulation part 42 and a third plastic encapsulation part 43 formed on the surface of the conductive substrate 1a, wherein the third plastic encapsulation part 43 is located between two adjacent circuit layers 5 on the same side of the conductive substrate 1a. The first plastic encapsulation part 41, the second plastic encapsulation part 42 and the third plastic encapsulation part 43 are combined to form the encapsulation layer 4 that completely covers the electronic component 3. Since the conductive substrate 1a is made of PPTC material, and the PPTC material uses a polymer as a matrix, the interface bonding force between the first plastic encapsulation part 41 and the second plastic encapsulation part 42 and the conductive substrate 1a can be improved, thereby avoiding the delamination phenomenon inside the encapsulation structure 100.

[0126] The material of the first plastic sealing part 41 can be selected from one of the resins such as epoxy resin, prepreg (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Specifically, in the present embodiment, the first plastic sealing part 41 is epoxy resin. The first plastic sealing part 41 can fill the opening 2 with the packaging material in a filling manner, which can improve the coating effect of the first plastic sealing part 41 on the electronic components 3, and can also increase the contact area between the first plastic sealing part 41 and the conductive substrate 1a, thereby improving the interface bonding force and reducing the defects such as pores caused by the lack of packaging material inside the opening 2.

[0127] The material of the second plastic sealing part 42 can be selected from one of epoxy resin, prepreg (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Specifically, in this embodiment, the second plastic sealing part 42 is a prepreg, and the second plastic sealing part 42 can be formed on the surface of the conductive substrate 1a by pressing. The conventional pressing method is simple in process and low in cost.

[0128] The material of the third plastic sealing part 43 can be selected from one of epoxy resin, prepreg (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Specifically, in this embodiment, the second plastic sealing part 42 is a prepreg, and the third plastic sealing part 43 can be formed on the surface of the second plastic sealing part 42 by pressing. The conventional pressing method is simple in process and low in cost.

[0129] like Figure 3As shown, the packaging structure 100 also includes a first conductive portion 61 and a second conductive portion 62 buried in the packaging layer 4, the first conductive portion 61 electrically connects the circuit layer 5 and the electronic component 3, and the second conductive portion 62 electrically connects the circuit layer 5 and the conductive substrate 1a.

[0130] like Figure 3 As shown, the packaging structure 100 a further includes a plurality of through holes 44 formed on the second plastic sealing part 42 and the third plastic sealing part 43 , and the plurality of through holes 44 are used to form the first conductive part 61 and the second conductive part 62 .

[0131] The plurality of through holes 44 are formed by lamination, exposure, development and etching, which is simple, easy to implement and low in cost. In other embodiments, the plurality of through holes 44 can also be formed by laser drilling or mechanical drilling.

[0132] The first conductive part 61 and the second conductive part 62 are both formed by electroplating copper in the corresponding through hole 44. The first conductive part 61 and the second conductive part 62 are formed by electroplating, which is simple in process, easy to implement, and low in cost; and the structural form of the first conductive part 61 and the second conductive part 62 can be designed according to actual needs, with little limitation. In other embodiments, the first conductive part 61 and the second conductive part 62 can also be formed by filling the conductive paste in the corresponding through hole 44 and curing it. The first conductive part 61 and the second conductive part 62 are formed by filling the conductive paste and curing it, which is simple in process, easy to operate, and low in cost. The conductive paste has more sufficient contact with the electronic component 3 and the conductive substrate 1a, which can improve the stability of the electrical connection.

[0133] like Figure 3 As shown, the packaging structure 100 a further includes a surface treatment layer 8 , and the surface treatment layer 8 is formed on the surface of the outermost circuit layer 5 and the third plastic sealing part 43 .

[0134] The material of the surface treatment layer 8 can be selected from thermosetting materials or light-curing materials with filling and protection functions, such as cover film (CVL), ink, pure glue, ABF resin and prepreg (PP). Specifically, the material of the surface treatment layer 8 is a cover film. The surface treatment layer 8 can also be an organic solderability preservative (OSP) or a chemical nickel gold layer.

[0135] The packaging structure 100a further includes a plurality of connection pads (not shown), which are arranged on the side of the outermost circuit layer 5 away from the electronic components 3, and are exposed on the surface treatment layer 8. Electrical connection with the circuit board can be achieved through the plurality of connection pads. At least one connection pad can be made of PPTC material. By arranging PPTC material at different locations, the structural design flexibility of the packaging structure 100a can be improved. The connection pad is made of PPTC material, which can have a faster response sensitivity to the current input by the power supply, thereby improving the over-current or over-temperature self-protection effect of the packaging structure 100a.

[0136] In the packaging structure 100a provided in this embodiment, the conductive substrate 1a is prepared by using PPTC material, which can increase the impedance when the packaging structure 100a is over-current or over-temperature, thereby reducing the current flowing through the electronic components 3 and preventing the electronic components 3 from being burned, thereby achieving the purpose of over-current or over-temperature self-protection; the conductive substrate 1a is directly prepared with PPTC material, and the thickness of the conductive substrate 1a will not increase compared with the conductive substrate 1', and there is no need to change the structural form of the original packaging structure 100', and the thickness of the packaging structure 100a will not increase, which is conducive to the packaging structure 100a being light, thin and short; and the preparation process is simple, the cost is low, and it is easy to mass produce.

[0137] See also Figure 4 The package structure 100b of another embodiment of the present application is different from the package structure 100a in the above embodiment in that: the conductive substrate 1b in this embodiment adopts a stacked multi-layer structure, and the conductive substrate 1b includes an insulating layer 11 and a conductive layer 12 stacked with the insulating layer 11, and the resistance of the conductive layer 12 increases with the increase of current or temperature. Specifically, the material of the conductive layer 12 is the PPTC material.

[0138] like Figure 4 As shown, the conductive substrate 1b is a three-layer structure, and the conductive layers 12 are formed on two opposite surfaces of the insulating layer 11, and the two conductive layers 12 can be electrically connected through vias.

[0139] The conductive layer 12 can be formed on the surface of the insulating layer 11 by lamination or coating. The lamination or coating molding process is simple, easy to mold, and low in cost.

[0140] The material of the insulating layer 11 can be selected from one of the resins such as epoxy resin, prepreg (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Specifically, the material of the insulating layer 11 is PI. Since the PPTC material uses a polymer as a matrix, the interface compatibility between the conductive layer 12 and the polymer insulating layer 11 is good. After lamination or coating, the bonding force between the conductive layer 12 and the insulating layer 11 is strong and not easy to delaminate, which is beneficial to improve the mechanical properties of the overall conductive substrate 1b.

[0141] Compared with the above-mentioned embodiment, the packaging structure 100b of this embodiment can reduce the amount of PPTC material while satisfying the purpose of circuit overcurrent or overtemperature self-protection through the multi-layer structure design. In particular, for thicker electronic components 3, the thickness of the conductive substrate 1b needs to be designed to be thicker. By designing the conductive substrate 1b as a structure in which the insulating layer 11 and the conductive layer 12 are stacked, the amount of PPTC material can be reduced, effectively reducing the cost, and at the same time, the resistance of the conductive substrate 1b when the circuit is working normally can be reduced, and the conductivity of the conductive substrate 1b when the circuit is working normally can be improved.

[0142] It is understandable that in other embodiments, the insulating layer 11 in the conductive substrate 1b may also be replaced by a conductive metal layer (not shown), thereby achieving the purpose of reducing the amount of PPTC material used.

[0143] See also Figure 5 The packaging structure 100c of another embodiment of the present application is different from the packaging structure 100a in the aforementioned embodiment in that: the conductive substrate 1 in this embodiment is made of conventional metal, and the resistance of the first conductive part 61c and the second conductive part 62c directly connecting the electronic component 3 and the conductive substrate 1, and the circuit layer 5c directly connected to the first conductive part 61c and the second conductive part 62c increase with the increase of current or temperature. Specifically, the first conductive part 61c, the second conductive part 62c and the circuit layer 5c are made of PPTC material.

[0144] The conductive substrate 1 may be made of copper.

[0145] The circuit layer 5c is formed on the surface of the second plastic sealing portion 42 by laminating or coating the PPTC material and curing it. The laminating or coating molding process is simple, easy to mold, and low in cost.

[0146] The first conductive portion 61c is formed by filling PPTC material in the through hole 44 of the corresponding electronic component 3 and curing it, and the second conductive portion 62c is formed by filling PPTC material in the through hole 44 of the corresponding conductive substrate 1 and curing it. The molding method is simple and low in cost.

[0147] Compared with the above-mentioned embodiments, the packaging structure 100c of this embodiment uses PPTC materials to make the first conductive part 61c, the second conductive part 62c and the circuit layer 5c that directly connect the electronic component 3 and the conductive substrate 1. When the circuit where the electronic component 3 is located has overcurrent or overtemperature, the current or excessive temperature will directly act on the first conductive part 61c, the second conductive part 62c and the circuit layer 5c, which can increase the reaction speed of the PPTC material to the temperature, so that the impedance of the PPTC material increases rapidly, the current decreases, and the electronic component 3 is prevented from being burned, thereby improving the effect of overcurrent or overtemperature self-protection. Moreover, PPTC materials can be introduced into different parts of the packaging structure according to actual needs, which improves the structural design flexibility of the packaging structure.

[0148] See also Figure 6 The packaging structure 100d of another embodiment of the present application is different from the packaging structure 100c provided in the above embodiment in that the resistance of each circuit layer 5c, the first conductive part 61c and the second conductive part 62c of the packaging structure 100d increases with the increase of current or temperature. Specifically, the materials of each circuit layer 5c, the first conductive part 61c and the second conductive part 62c are all PPTC materials.

[0149] Increasing the resistance of each circuit layer 5c, the first conductive part 61c and the second conductive part 62c in the packaging structure 100d as the current or temperature increases can increase the effect of overcurrent or overtemperature self-protection, and can improve the effect of overcurrent or overtemperature self-protection of the packaging module 100, which is particularly suitable for high-power devices, and has simple molding and low cost. In particular, the first conductive part 61c is directly connected to the electronic component 3, and can directly sense the temperature of the electronic component 3 and whether the current flowing through the electronic component 3 is too large, so as to react quickly, reduce the risk of burning the electronic component 3, and improve the yield of the packaging structure 100d.

[0150] See also Figure 7The packaging structure 100e of another embodiment of the present application is different from the packaging structure 100c in the above-mentioned embodiment in that: the circuit layer 5e in this embodiment includes a first layer 51e and a second layer 52e stacked in layers, and the resistance of the first layer 51e increases with the increase of current or temperature. Specifically, the material of the first layer 51e is PPTC material.

[0151] The second layer 52e is formed on the surface of the first layer 51e by electroplating, and the forming method is simple. Specifically, the second layer 52e is a copper layer.

[0152] The circuit layer 5e adopts a multi-layer structural design, in which the first layer 51e is made of PPTC material, which can not only achieve the purpose of over-current or over-temperature self-protection, but also reduce the amount of PPTC material used, thereby reducing costs. Moreover, by replacing part of the PPTC material with a metal with better conductivity, the resistance of the circuit layer 5e under normal working conditions can also be reduced.

[0153] See also Figure 8 The packaging structure 100f of another embodiment of the present application is different from the packaging structure 100e in the above-mentioned embodiment in that: the circuit layer 5f in this embodiment includes a first layer 51f and a second layer 52f stacked in layers, the resistance of the second layer 52f increases with the increase of current or temperature, and the first conductive part 61 and the second conductive part 62 are made of metal. Specifically, the second layer 52f is made of PPTC material.

[0154] The first layer 51f is formed on the surface of the second plastic sealing portion 42 by electroplating, and the molding method is simple. Specifically, the first layer 51f is a copper layer.

[0155] The circuit layer 5f adopts a multi-layer structural design, in which the first layer 51f is a copper layer, and the second layer 52f is made of PPTC material, which can not only achieve the purpose of over-current or over-temperature self-protection, but also reduce the amount of PPTC material used, thereby reducing costs. Moreover, by replacing part of the PPTC material with copper with better conductivity, the resistance of the circuit layer 5f under normal working conditions can also be reduced.

[0156] See also Fig. 9, the package structure 100g of another embodiment of the present application is different from the package structure 100a and the package structure 100d in the above-mentioned embodiment in that: the present embodiment combines the package structure 100a provided in the above-mentioned embodiment with the package structure 100d provided in the above-mentioned embodiment, wherein the resistance of the conductive substrate 1a, the circuit layer 5c, the first conductive part 61c and the second conductive part 62c increases with the increase of current or temperature. Specifically, the conductive substrate 1a, the circuit layer 5c, the first conductive part 61c and the second conductive part 62c are all made of PPTC material.

[0157] The conductive substrate 1a, the circuit layer 5c, the first conductive part 61c and the second conductive part 62c in the packaging structure 100g are all made of PPTC material, which can increase the effect of over-current or over-temperature self-protection, especially suitable for high-power devices.

[0158] See also Fig.10 , the packaging structure 100h of another embodiment of the present application is different from the packaging structure 100g in the above-mentioned embodiment in that: the circuit layer 5f of each layer of the present embodiment includes a first layer 51f and a second layer 52f which are stacked, the resistance of the second layer 52f increases with the increase of current or temperature, and the material of the first conductive part 61 and the second conductive part 62 is metal, such as copper. Specifically, the material of the second layer 52f is PPTC material.

[0159] The conductive substrate 1a and all the second layers 52f in the packaging structure 100h are made of PPTC material, which can increase the effect of over-current or over-temperature self-protection, especially for high-power devices; at the same time, the circuit layer 5f adopts a multi-layer structure design, in which the first layer 51f is a copper layer, and the second layer 52f is made of PPTC material, which can not only achieve the purpose of over-current or over-temperature self-protection, but also reduce the amount of PPTC material, thereby reducing costs. Moreover, by replacing part of the PPTC material with copper with better conductivity, the resistance of the circuit layer 5f under normal working conditions can also be reduced.

[0160] See also Fig.11 , a packaging structure 100i in another embodiment of the present application is different from the packaging structure 100a in the aforementioned embodiment in that: the packaging structure 100i in this embodiment includes a first area A and a second area B connected to the first area A, the electronic component 3 is located in the first area A, the second area B is located at the outer edge of the first area A away from the electronic component 3, and the resistance of the conductive substrate 1i in the first area A increases with the increase of current or temperature. Specifically, the material of the conductive substrate 1i in the first area A includes the PPTC material.

[0161] PPTC material is arranged in the first zone A. The PPTC material can respond quickly to the large current flowing through the electronic component 3 or the excessive temperature around the electronic component 3, thereby improving the effect of over-current or over-temperature self-protection; at the same time, the amount of PPTC material can be reduced and the cost can be reduced; in addition, the local use of PPTC material does not require changing the original structure and line materials of other areas, and will not affect the conductivity of the lines in other areas.

[0162] See also Fig.12 , a packaging structure 100j of another embodiment of the present application is different from the packaging structure 100i in the above-mentioned embodiment in that: the conductive substrate 1 in this embodiment adopts a conventional structure and material, the packaging structure 100j includes a first area A and a second area B connected to the first area A, the electronic component 3 is located in the first area A, the second area B is located at the outer edge of the first area A away from the electronic component 3, the circuit layer 5j includes a first circuit 51j corresponding to the first area A and a second circuit 52j connected to the first circuit 51j, wherein the resistance of the first circuit 51j increases with the increase of current or temperature. Specifically, the material of the first circuit 51j includes the PPTC material.

[0163] PPTC material is set in a local area of ​​the circuit layer 5j near the electronic component 3. The PPTC material can respond quickly to the large current flowing through the electronic component 3 or the excessive temperature around the electronic component 3, thereby improving the effect of over-current or over-temperature self-protection; at the same time, it can also reduce the amount of PPTC material and reduce costs; in addition, the local use of PPTC material does not require changing the original structure and circuit materials of other areas, and will not affect the conductivity of the circuits in other areas.

[0164] See also Fig.13 A packaging structure 100k of another embodiment of the present application is different from the packaging structure 100a in the aforementioned embodiment in that the electronic components 3 in this embodiment are arranged on the surface of the conductive substrate 1k and buried in the packaging layer 4. By directly installing the electronic components 3 on the conductive substrate 1k, the process is simple and easy to operate, and there is no need to open the conductive substrate 1k, thereby reducing the difficulty of packaging.

[0165] Combined with reference Figure 1 The package structure 100a (or 100b / 100c / 100d / 100e / 100f / 100g / 100h / 100i / 100j / 100k) provided in the above embodiments of the present application can be applied to Figure 1In the packaging module 1000, by introducing PPTC materials at different locations in the packaging structure 100a, the packaging structure 100a has an over-current or over-temperature self-protection function. When the packaging structure 100a is electrically connected to the circuit board 200 through a plurality of connecting parts 300, it can not only reduce the risk of burning of the electronic components 3 inside the packaging structure 100a, but also further reduce the risk of burning of the circuit board 200 due to over-current or over-temperature, thereby improving the performance stability of the packaging module 1000, and further improving the yield and service life of the packaging module 1000.

[0166] See also Fig.14 Another embodiment of the present application provides a packaging module 2000, which is different from the packaging module 1000 in the above embodiment in that: at least one connection part 3001 is made of PPTC material, and the conductive substrate 1 and the circuit layer 5 in the packaging structure 1001 are made of conventional metal materials. Specifically, the material of the connection part 3001 corresponding to the power input terminal (Vin terminal) is PPTC material.

[0167] When the packaging structure 100l is electrically connected to the circuit board 200 through the connecting part 300l, the input current of the power input end (Vin end) is the largest. The connecting part 300l corresponding to the Vin end is made of PPTC material, which can improve the response speed of the PPTC material, thereby more effectively achieving the purpose of over-current or over-temperature self-protection.

[0168] An embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100a, which comprises the following steps:

[0169] S101: Fig.15 As shown, a conductive substrate 1a is provided, and the material of the conductive substrate 1a is PPTC material.

[0170] S102: Fig.16 As shown, an opening 2 is formed on the conductive substrate 1a.

[0171] In this embodiment, the opening 2 is formed by lamination, exposure, development and etching. Since the conductive substrate 1a is made of PPTC material as a whole, the opening 2 is formed by etching, which is simple, easy to implement and low in cost. In other embodiments, the opening 2 can also be formed by laser drilling or mechanical drilling.

[0172] S103, such as Fig.17 As shown, a carrier film 20 is attached to the conductive substrate 1 a , and the side wall of the opening 2 and the surface of the carrier film 20 together form a receiving cavity 30 .

[0173] By adding the carrier film 20 , it can play a supporting role for the subsequent embedded electronic components 3 .

[0174] S104, such as Fig.18 As shown, the electronic component 3 is arranged in the accommodating cavity 30 .

[0175] Usually, the thickness of the embedded electronic component 3 needs to be less than or equal to the thickness of the conductive substrate 1 a, so that the electronic component 3 can be completely embedded in the conductive substrate 1 a.

[0176] S105, such as Fig.18 and Fig.19 As shown, the packaging material is filled into the accommodating cavity 30 and cured to form a first plastic sealing portion 41 , wherein the first plastic sealing portion 41 completely covers the upper surface and the side surface of the electronic component 3 .

[0177] The packaging material used in the first plastic sealing part 41 can be selected from one of the resins such as epoxy resin, prepreg (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Specifically, in the present embodiment, the first plastic sealing part 41 is epoxy resin. By filling the packaging material into the accommodating cavity 30, the coating effect of the first plastic sealing part 41 on the electronic component 3 can be improved, and the contact area between the first plastic sealing part 41 and the conductive substrate 1a can be increased, thereby improving the interface bonding force and reducing the defects such as pores caused by the lack of packaging material inside the opening 2.

[0178] S106, such as Fig. 20 As shown, the carrier film 20 is removed.

[0179] S107, such as Fig.21 As shown, second plastic sealing parts 42 are respectively formed on two opposite surfaces of the conductive substrate 1a, and the second plastic sealing parts 42 cover the surface of the first plastic sealing part 41 and the bottom surface of the electronic component 3. The first plastic sealing part 41 and the second plastic sealing part 42 completely cover the electronic component 3.

[0180] The above method realizes the embedding of the electronic components 3. The embedding method is conducive to reducing the thinness and miniaturization of the packaging structure 100a, and can improve the packaging density of the electronic components 3 in the packaging structure 100a.

[0181] S108, such as Fig. 22 As shown, a plurality of through holes 44 are formed on the second plastic sealing portion 42 , and two opposite surfaces of the conductive substrate 1 a and one surface of the electronic component 3 are exposed in the through holes 44 .

[0182] The plurality of through holes 44 are formed by lamination, exposure, development and etching, which is simple, easy to implement and low in cost. In other embodiments, the plurality of through holes 44 can also be formed by laser drilling or mechanical drilling.

[0183] S109, such as Fig.23 As shown, copper is electroplated in the through hole 44 corresponding to the electronic component 3 to form a first conductive part 61, copper is electroplated in the through hole 44 corresponding to the conductive substrate 1a to form a second conductive part 62, and copper is electroplated on the surface of the second plastic sealing part 42 to form a copper layer 40, and the copper layer 40 is electrically connected to the first conductive part 61 and the second conductive part 62, respectively.

[0184] S110, such as Fig.24 As shown, the copper layer 40 is patterned to form a circuit layer 5 .

[0185] The specific patterning method can be a conventional circuit manufacturing method, that is, forming the circuit layer 5 by lamination, exposure, development and etching.

[0186] S111, such as Fig.25 and Fig.26 As shown, a third plastic sealing portion 43 is formed on the surface of the second plastic sealing portion 42, and another plurality of through holes 44 are formed on the third plastic sealing portion 43. Copper is electroplated in the other plurality of through holes 44 to form another plurality of second conductive portions 62, and then another copper layer 40 is formed on the surface of the third plastic sealing portion 43.

[0187] S112, such as Figure 3 As shown, the other copper layer 40 is patterned to form an outermost circuit layer 5, and a surface treatment layer 8 is formed on the surface of the outermost circuit layer 5 and the surface of the third plastic sealing part 43, thereby obtaining the packaging structure 100a.

[0188] The preparation method of the packaging structure 100a is simple and easy to implement. There is no need to change the structural form of the original packaging structure, and no special molding equipment and special processes are required. The preparation method is simple, easy to implement, low in cost, and easy to mass produce.

[0189] An embodiment of the present application further provides a method for preparing the above-mentioned package structure 100b. The difference between the method for preparing the package structure 100b of this embodiment and the method for preparing the package structure 100a of the above-mentioned embodiment lies in the following steps:

[0190] S201, combined Figure 4 As shown, a conductive substrate 1b is provided. The conductive substrate 1b includes an insulating layer 11 and a conductive layer 12 stacked with the insulating layer 11. The conductive layer 12 is made of the PPTC material.

[0191] The conductive layer 12 can be formed on the surface of the insulating layer 11 by lamination or coating. The lamination or coating molding process is simple, easy to mold, and low in cost.

[0192] The material of the insulating layer 11 can be selected from one of the resins such as epoxy resin, prepreg (PP), BT resin, polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Specifically, the material of the insulating layer 11 is PI. Since the PPTC material uses a polymer as a matrix, the interface compatibility between the conductive layer 12 and the polymer insulating layer 11 is good. After lamination or coating, the bonding force between the conductive layer 12 and the insulating layer 11 is strong and not easy to delaminate, which is beneficial to improve the mechanical properties of the overall conductive substrate 1b.

[0193] For other steps, please refer to the aforementioned method for preparing the packaging structure 100a.

[0194] Combination Figure 5 As shown, an embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100c. The difference between the method for preparing the packaging structure 100c of this embodiment and the method for preparing the packaging structure 100a of the aforementioned embodiment is that: the material of the provided conductive substrate 1 is copper; when making the first conductive part 61c directly connected to the electronic component 3, it is formed by filling PTTC material, and the material of the second conductive part 62 is copper; the circuit layer 5c directly connected to the first conductive part 61c is made of PPTC material, and the method for making other circuit layers 5 can refer to the method in the aforementioned packaging structure 100a. The circuit layer 5c is formed by pressing or coating PTTC material on a surface of the packaging layer 4 and curing it to form a PPTC material layer, and then patterning the PPTC material layer. For other steps, please refer to the method for preparing the aforementioned packaging structure 100a.

[0195] Combination Figure 6As shown, an embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100d. The difference between the method for preparing the packaging structure 100d of this embodiment and the method for preparing the packaging structure 100c in the aforementioned embodiment is that the material of the first conductive part 61c, the second conductive part 62c and all the circuit layers 5c are PTTC materials. For the specific molding method, please refer to the aforementioned method.

[0196] Combination Figure 7 As shown, an embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100e. The difference between the method for preparing the packaging structure 100e of this embodiment and the method for preparing the packaging structure 100c in the aforementioned embodiment is that the material of the first conductive part 61c directly connected to the electronic component 3 is PPTC material, and the circuit layer 5e directly connected to the first conductive part 61c includes a first layer 51e and a second layer 52e stacked in layers, and the material of the first layer 51e is PPTC material. For the specific molding method of the first layer 51e, please refer to the aforementioned embodiment, which will not be described in detail here. The second layer 52e is formed on the surface of the first layer 51e by copper electroplating.

[0197] Combination Figure 8 As shown, an embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100f. The difference between the method for preparing the packaging structure 100f of this embodiment and the method for preparing the packaging structure 100e of the aforementioned embodiment is that: the first conductive part 61 directly connected to the electronic component 3 is formed by copper electroplating in the through hole 44, wherein a circuit layer 5f close to the electronic component 3 includes a first layer 51f and a second layer 52f stacked together, the first layer 51f is formed on the surface of the packaging layer 4 by copper electroplating, the material of the second layer 52f is PPTC material, and the specific molding method of the second layer 52f please refer to the aforementioned embodiment, which will not be elaborated here.

[0198] An embodiment of the present application further provides a method for preparing the above-mentioned package structure 100g. The difference between the method for preparing the package structure 100g of this embodiment and the method for preparing the package structure 100a of the above-mentioned embodiment lies in the following steps:

[0199] S201 to S208 refer to the preparation steps S101 to S108 of the aforementioned package structure 100 a.

[0200] S209, such as Fig. 27As shown, PPTC material is filled in the through hole 44 corresponding to the electronic component 3 and cured to form a first conductive part 61c, PPTC material is filled in the through hole 44 corresponding to the conductive substrate 1a and cured to form a second conductive part 62c, and a PPTC material layer 40c is formed on the surface of the second plastic sealing part 42 and cured, and the PPTC material layer 40c is electrically connected to the first conductive part 61c and the second conductive part 62c.

[0201] Specifically, the PPTC material layer 40 c is formed by pressing or coating the PPTC material on the surface of the second plastic sealing portion 42 .

[0202] S210, such as Fig. 27 and Fig.28 As shown, the PPTC material layer 40c is patterned to form a circuit layer 5c. The specific patterning method can be a conventional circuit manufacturing method, that is, the circuit layer 5c is formed by lamination, exposure, development and etching.

[0203] S211, such as Fig.29 and Fig.30 As shown, a third plastic sealing portion 43 and another PPTC material layer 40c are formed on the surface of the circuit layer 5c by building up layers. For the specific molding method, please refer to the above description.

[0204] S212, combined Fig. 9 and Fig.30 As shown, the other PPTC material layer 40c is patterned to form an outermost circuit layer 5c, and a surface treatment layer 8 is formed on the surface of the outermost circuit layer 5c and the surface of the third plastic sealing part 43, thereby obtaining the packaging structure 100g.

[0205] An embodiment of the present application further provides a method for preparing the above-mentioned package structure 100h. The difference between the method for preparing the package structure 100h of this embodiment and the method for preparing the package structure 100a of the above-mentioned embodiment lies in the following steps:

[0206] S301 to S308 refer to the preparation steps S101 to S108 of the aforementioned package structure 100 a.

[0207] S309, such as Fig.31 As shown, copper is electroplated in the through hole 44 corresponding to the electronic component 3 to form a first conductive part 61, copper is electroplated in the through hole 44 corresponding to the conductive substrate 1a to form a second conductive part 62, copper is electroplated on the surface of the second plastic sealing part 42 to form a copper layer 50, and a PPTC material layer 60 is formed on the surface of the copper layer 50 and solidified.

[0208] Specifically, the PPTC material layer 60 is formed by laminating or coating the PPTC material.

[0209] S310, such as Fig.32 As shown, combined Fig.31 , the PPTC material layer 60 is patterned to form the second layer 52f, and the copper layer 50 is patterned to form the first layer 51f, wherein the first layer 51f and the second layer 52f constitute the circuit layer 5f. The specific patterning method can be a conventional circuit manufacturing method, that is, the first layer 51f and the second layer 52f are formed by lamination, exposure, development and etching. It can be understood that the first layer 51f and the second layer 52f can be patterned at the same time or in steps. In this embodiment, the copper layer 50 and the PPTC material layer 60 are patterned at the same time to form the circuit layer 5f.

[0210] S311, such as Fig.33 and Fig.34 As shown, a third plastic sealing portion 43, another copper layer 50 and another PPTC material layer 60 are formed on the surface of the circuit layer 5f by building up layers. For the specific forming method, please refer to the above.

[0211] S312, combined Fig.10 and Fig.34 As shown, the other copper layer 50 and the other PPTC material layer 60 are patterned to form an outermost circuit layer 5f, and a surface treatment layer 8 is formed on the surface of the outermost circuit layer 5f and the surface of the third plastic sealing part 43, thereby obtaining the packaging structure 100h.

[0212] An embodiment of the present application further provides a method for preparing the above-mentioned package structure 100i. The difference between the method for preparing the package structure 100i of this embodiment and the method for preparing the package structure 100a of the above-mentioned embodiment lies in the following steps:

[0213] S401, such as Fig.35 As shown, a metal plate 7 is provided, wherein the metal plate 7 includes a first region A and a second region B connected to the first region A.

[0214] S402, such as Fig.36 As shown, corresponding to the first area A, a window 70 is opened on the metal plate 7 .

[0215] S403, such as Fig.37 As shown, a carrier film 20 is attached to the surface of the metal plate 7 .

[0216] S404, such as Fig.38 As shown, the PPTC material is filled in the opening 70 and cured to form the third conductive portion 9 .

[0217] S405, such as Fig.39As shown, an opening 2 is opened on the third conductive portion 9 to obtain a conductive substrate 1i.

[0218] The subsequent preparation method of the package structure 100i is the same as the preparation method of the package structure 100a, please refer to the aforementioned method.

[0219] Combination Fig.12 As shown, an embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100j. The difference between the method for preparing the packaging structure 100j of this embodiment and the method for preparing the packaging structure 100i of the aforementioned embodiment is that: the packaging structure 100j includes a first area A. During the molding process, the circuit layer 5j first forms a first circuit 51j by laminating or coating PTTC material and curing the first area A, and then electroplating copper in other areas outside the first circuit 51j to form a second circuit 52j. For other preparation methods, please refer to the preparation method of the packaging structure 100c provided in the aforementioned embodiment.

[0220] Combination Fig.13 As shown, an embodiment of the present application also provides a method for preparing the above-mentioned packaging structure 100k. The difference between the method for preparing the packaging structure 100k of this embodiment and the method for preparing the packaging structure 100a of the aforementioned embodiment is that: the conductive substrate 1k of this embodiment does not need to have an opening for installing the electronic component 3, and the electronic component 3 can be directly welded on the conductive substrate 1k. The preparation methods of other structures refer to the preparation methods of the aforementioned embodiments.

[0221] Combination Figure 1 As shown, an embodiment of the present application further provides a method for preparing a packaging module 1000, and the specific steps are: forming a connecting portion 300 between the packaging structure 100a (100b / 100c / 100d / 100e / 100f / 100g / 100h / 100i / 100j / 100k) provided in the aforementioned embodiment and the circuit board 200 by welding, thereby obtaining the packaging module 1000.

[0222] Combination Fig.14 As shown, another embodiment of the present application further provides a method for preparing a packaging module 2000, and the specific steps are: coating or spot-coating the power input end (Vin end) of the packaging structure 100l with PTTC material to form a connecting portion 300l, and the remaining connecting portions 300 are formed by conventional welding, and electrically connected to the circuit board 200 through the connecting portion 300l, thereby obtaining the packaging module 2000.

[0223] It should be noted that the above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application; the implementation methods of the present application and the features in the implementation methods can be combined with each other without conflict. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A packaging structure, characterized in that: include: A conductive substrate, comprising an insulating layer and a conductive layer located on a surface of the insulating layer; An encapsulation layer, located on the surface of the conductive substrate; Electronic components, located in the packaging layer; as well as A circuit layer is located on the surface of the conductive substrate, and the circuit layer is electrically connected to the conductive substrate and the electronic components respectively; The resistance of the conductive layer and / or the circuit layer increases with the increase of current or temperature, and the conductive layer and / or the circuit layer are made of positive temperature coefficient (PTC) material.

2. The packaging structure according to claim 1, characterized in that: The circuit layer includes a first layer arranged close to the electronic components and a second layer arranged on a surface of the first layer away from the electronic components. The resistance of the first layer and / or the second layer increases with increasing current or temperature.

3. The packaging structure according to claim 1, characterized in that: The packaging structure includes a first area and a second area connected to the first area, the electronic components are located in the first area, the second area is located at the outer edge of the first area away from the electronic components, and the resistance of the conductive substrate and / or the circuit layer in the first area increases with the increase of current or temperature.

4. The packaging structure according to claim 1, characterized in that: The packaging structure also includes a first conductive part and a second conductive part, wherein the first conductive part and the second conductive part are both located in the packaging layer, the first conductive part electrically connects the circuit layer and the electronic components, and the second conductive part electrically connects the circuit layer and the conductive substrate, and the resistance of the first conductive part and / or the second conductive part increases with the increase of current or temperature.

5. The packaging structure according to claim 1, characterized in that: The packaging structure further includes a plurality of connection pads disposed on the circuit layer away from the surface of the electronic components, and the resistance of at least one of the connection pads increases with the increase of current or temperature.

6. The packaging structure according to claim 1, characterized in that: The conductive substrate comprises an opening, and the electronic component is located in the opening.

7. A packaging module, characterized in that: The invention comprises a packaging structure, a circuit board and a plurality of connection parts, wherein the plurality of connection parts electrically connect the packaging structure and the circuit board, and the packaging structure is the packaging structure according to any one of claims 1 to 6.

8. The packaging module according to claim 7, characterized in that: The resistance of the connection portion increases with the increase of current or temperature.

9. An electronic device, characterized in that: Comprising the packaging module as described in claim 7 or 8.

10. A method for preparing a packaging structure, characterized in that: include: forming a packaging layer on a surface of a conductive substrate, wherein the conductive substrate comprises an insulating layer and a conductive layer disposed on at least one surface of the insulating layer, wherein electronic components are packaged in the packaging layer; and A circuit layer is formed on the surface of the conductive substrate, wherein the circuit layer is electrically connected to the conductive substrate and the electronic components respectively. The resistance of the conductive layer and / or the circuit layer increases with the increase of current or temperature. The conductive layer and / or the circuit layer are made of PTC material, so as to obtain the packaging structure.

11. The method for preparing a packaging structure according to claim 10, characterized in that: The circuit layer includes a first layer and a second layer, and the resistance of the first layer and / or the second layer increases with the increase of current or temperature. The method for preparing the circuit layer comprises the steps of: forming the first layer on the surface of the conductive substrate, wherein the resistance of the first layer increases with the increase of current or temperature; Disposing metal on the surface of the first layer to form the second layer; as well as Patterning the first layer and the second layer to form the circuit layer; Alternatively, the method for preparing the circuit layer comprises the steps of: Disposing metal on the surface of the conductive substrate to form the first layer; forming the second layer on the surface of the first layer, wherein the resistance of the second layer increases with the increase of current or temperature; as well as The first layer and the second layer are patterned to form the circuit layer.

12. The method for preparing a packaging structure according to claim 10, characterized in that: The packaging structure includes a first area and a second area connected to the first area, the electronic component is located in the first area, the second area is located at the outer edge of the first area away from the electronic component, the conductive substrate includes a third conductive part corresponding to the first area, and the resistance of the third conductive part increases with the increase of current or temperature. The preparation method of the conductive substrate includes the steps of: A window is formed through the metal plate; Laminating a carrier film on the metal plate; Disposing PPTC material in the opening and curing it to form the third conductive part; as well as The carrier film is removed to obtain the conductive substrate.

13. The method for preparing a packaging structure according to claim 10, characterized in that: The packaging structure includes a first area and a second area connected to the first area, the electronic components are located in the first area, the second area is located at the outer edge of the first area away from the electronic components, and the resistance of the circuit layer in the first area increases with the increase of current or temperature.

14. The method for preparing a packaging structure according to claim 10, characterized in that: The preparation method further comprises the steps of: A first conductive part and a second conductive part are provided in the packaging layer, the first conductive part electrically connects the circuit layer and the electronic component, the second conductive part electrically connects the circuit layer and the conductive substrate, and the resistance of the first conductive part and / or the second conductive part increases with the increase of current or temperature.

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