A heat dissipating device and an electronic device comprising the same

Abstract

The application discloses a heat dissipation device and an electronic device comprising the same. The heat dissipation device comprises a substrate and a composite film layer which is combined on the surface of the substrate. The side of the composite film layer which is far away from the substrate is used to adhere and fix the electronic component. The material of the composite film layer is insulating material, and the material of the substrate is ceramic. In this way, the ceramic and the composite film layer are both insulators. Even if the thickness of the composite film layer is thin, the composite film layer will not be broken down, and the substrate and the lead frame will not be conducted. The ceramic has good heat conduction performance, and can dissipate the heat generated by the electronic component in time. The ceramic is resistant to chemical corrosion and will not be oxidized. Moreover, the ceramic material has high strength, and the surface of the substrate will not be scratched. The ceramic material will not be warped, and thus the plastic sealing material will not overflow to the surface of the substrate to affect the appearance of the electronic device. Furthermore, the ceramic is inorganic material, and the ceramic used as the substrate is more in line with the concept of environmental protection.

Description

Technical Field

[0001] This invention relates to the field of heat dissipation technology for electronic devices, and more specifically, to a heat dissipation device and an electronic device including the heat dissipation device. Background Technology

[0002] To ensure the normal and reliable operation of electronic devices, heat dissipation devices are needed to dissipate the heat generated by semiconductor devices. Typically, a heat dissipation device for electronic devices includes a substrate and an insulating layer disposed on the upper surface of the substrate for connecting a lead frame to the semiconductor device.

[0003] Currently, most substrates used are copper or aluminum substrates. Copper substrates are prone to oxidation under high temperatures, and they also have poor strength and are easily scratched. Aluminum substrates are prone to warping, have low strength, and low thermal conductivity, which is not conducive to heat dissipation of high-power devices. Both copper and aluminum are conductive materials, and the insulating layer on the surface of copper or aluminum substrates must meet a certain thickness to ensure the insulation characteristics of the heat dissipation device, which reduces the safety and reliability of electronic devices. When molding the substrate and lead frame together, if the copper or aluminum substrate is warped, the molding compound will overflow to the bottom surface of the substrate, increasing the appearance failure rate of electronic devices. Scratches and oxidation on the surface of the copper substrate will also lead to poor appearance of electronic devices.

[0004] Therefore, how to solve the problems of needing a thicker insulating layer on the upper surface of the substrate of the heat dissipation device to ensure the safety of electronic devices, and the problems of substrate warping, easy oxidation and scratches leading to poor appearance of electronic devices, has become an important technical problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a heat dissipation device and an electronic device including the heat dissipation device, solving the problems that the upper surface of the substrate of the heat dissipation device needs a thick insulating layer to ensure the safety of the electronic device, and that the substrate has warpage, is easily oxidized and scratched, resulting in poor appearance of the electronic device. The various technical effects of the preferred solutions among the many technical solutions provided by this invention are described in detail below.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] The present invention provides a heat dissipation device, including a substrate and a composite film layer laminated on the surface of the substrate. The side of the composite film layer away from the substrate is used to attach and fix electronic components. The composite film layer is made of an insulating material, and the substrate is made of ceramic.

[0008] Preferably, the composite film layer includes a support layer laminated on the surface of the substrate and an adhesive layer laminated on the side of the support layer away from the substrate. The side of the adhesive layer away from the support layer is used to attach and fix electronic components. The hardness of the support layer is greater than that of the adhesive layer.

[0009] Preferably, the materials of the support layer and the adhesive layer both include epoxy resin, filler and curing agent, wherein the filler is silicon oxide or aluminum oxide.

[0010] Preferably, the curing rate of the epoxy resin in the support layer is δ1, where δ1 > 95%; and the curing rate of the epoxy resin in the adhesive layer is δ2, where 30% < δ2 < 80%.

[0011] Preferably, the adhesive layer has a protective film on the side away from the support layer, and the protective film is detachably connected to the adhesive layer.

[0012] Preferably, the protective film has an adhesive layer to connect the protective film to the adhesive layer.

[0013] The present invention also provides an electronic device, including the above-described heat dissipation device and electronic components, wherein the heat dissipation device is used to dissipate the heat generated by the electronic components.

[0014] Preferably, the electronic component includes a lead frame and a semiconductor device. The lead frame includes a frame body and a base island connected to the frame body. The semiconductor device and the heat dissipation device are respectively disposed on both sides of the base island.

[0015] Preferably, the base island includes a connection portion connected to the pins of the semiconductor device, and the surface of the connection portion is provided with a plating layer, the plating layer being made of silver.

[0016] Preferably, the surface of the lead frame is provided with a corrosion-resistant layer to prevent oxidation of the lead frame.

[0017] Preferably, the corrosion-resistant layer is made of nickel.

[0018] Preferably, a stepped structure is formed at the connection between the base island and the frame body, and the plane where the base island is located is located between the plane where the heat dissipation device and the frame body are located.

[0019] Preferably, the electronic device is an IPM module (Intelligent Power Module).

[0020] In the technical solution provided by this invention, the heat dissipation device includes a substrate and a composite film layer laminated on the surface of the substrate. The side of the composite film layer away from the substrate is attached to and fixedly connected to the electronic component. The composite film layer is made of an insulating material, and the substrate is made of ceramic. Ceramic has the characteristics of insulation, thermal conductivity, high temperature resistance, and chemical corrosion resistance, and is widely used in the microelectronics industry. Both ceramic and the composite film layer are insulators. Ceramic has a high breakdown voltage, which can prevent damage caused by any short circuit. Even if the composite film layer is thin, there will be no phenomenon of the composite film layer being broken down and the substrate and lead frame becoming conductive. Ceramic has good thermal conductivity, which can dissipate the heat generated by the electronic component in a timely manner. Ceramic is resistant to chemical corrosion and will not be oxidized. Moreover, ceramic material has high strength, so there will be no scratches on the substrate surface. Ceramic material does not warp, and the substrate can fit with the molding die without gaps between them, preventing the molding compound from flowing into the gap between the substrate and the die during the molding process, thereby preventing the molding compound from overflowing onto the surface of the substrate and affecting the appearance of the electronic device. Ceramic is an inorganic material, and using ceramic as a substrate is more in line with the concept of environmental protection. This design solves the problems of needing a thicker insulating layer on the upper surface of the substrate to ensure the safety of electronic devices, as well as the issues of substrate warping, easy oxidation, and scratches that lead to poor appearance of electronic devices. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the heat dissipation device in an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the electronic device in an embodiment of the present invention.

[0024] Figure 3 This is a structural schematic diagram of the connection between the frame body and the base island in an embodiment of the present invention.

[0025] In the picture:

[0026] 1-Lead frame, 11-Frame body, 12-Base island, 121-Connector, 2-Heat dissipation device, 21-Substrate, 22-Support layer, 23-Adhesion layer, 24-Protective film, 3-Semiconductor device. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0028] The purpose of this specific embodiment is to provide a heat dissipation device. The substrate of the heat dissipation device is made of ceramic, which improves the electrical safety of electronic devices. At the same time, ceramic has low warpage and good chemical stability, which reduces the appearance failure rate of electronic devices.

[0029] Hereinafter, embodiments will be described with reference to the accompanying drawings. Furthermore, the embodiments shown below do not limit the scope of the invention as described in the claims. Additionally, the complete contents of the configurations represented in the embodiments below are not limited to those necessary for the solution of the invention described in the claims.

[0030] Please see Figure 1 In this embodiment, the heat dissipation device includes a substrate 21 and a composite film layer disposed on the upper surface of the substrate 21. The composite film layer is bonded to the substrate 21, and the side of the composite film layer away from the substrate 21 is used to attach to electronic components. The electronic components are fixedly connected to the substrate 21 through the composite film layer. The heat generated by the electronic components is transferred to the heat dissipation device 2, and the heat is dissipated through the heat dissipation device 2. The composite film layer is made of an insulating material, and the substrate 21 is made of ceramic. Both the composite film layer and the substrate 21 are insulators to ensure the electrical safety of the electronic devices.

[0031] Ceramic exhibits excellent insulation and high breakdown voltage, preventing breakdown and conduction between electronic components and substrate 21 even with a thin composite film. It is also resistant to chemical corrosion and possesses excellent chemical stability, resisting oxidation and other chemical reactions. Furthermore, its high strength prevents surface scratches that could compromise the appearance of electronic devices. Ceramic demonstrates good thermal conductivity and high-temperature resistance, effectively dissipating heat generated by electronic components. Its smooth, warp-free surface ensures a tight fit between substrate 21 and the molding die during the encapsulation process of the heat sink 2 and electronic components. This prevents molding compound from seeping into the gap between substrate 21 and the molding die, thus avoiding excess molding compound on the substrate 21 surface and reducing the appearance failure rate of the heat sink 2 and electronic components.

[0032] With this configuration, the substrate 21 is made of ceramic. Ceramic itself has the characteristics of insulation, thermal conductivity, high temperature resistance, chemical corrosion resistance, high strength, and low warpage. It can ensure the electrical safety and reliability of electronic devices without the need for a thick composite film layer. The substrate 21 is not oxidized and is not easily scratched, avoiding the phenomenon of glue overflow during the molding process and reducing the appearance failure rate of electronic devices.

[0033] It should be noted that the electronic components include a lead frame 1 and a semiconductor device 3 connected to the lead frame 1. The semiconductor device 3 may be, but is not limited to, a semiconductor chip. The heat generated by the semiconductor chip is transferred to the heat dissipation device 2. The composite film layer serves two purposes: insulation and heat conduction, and fixing the lead frame 1. The coefficient of thermal expansion of ceramic is close to that of the semiconductor chip. By making the substrate 21 a ceramic material, damage to the semiconductor chip due to thermal stress can also be avoided.

[0034] In a preferred embodiment, the composite film layer includes a support layer 22 and an adhesive layer 23. The support layer 22 is laminated to the upper surface of the substrate 21, and the adhesive layer 23 is laminated to the upper surface of the support layer 22. The side of the adhesive layer 23 away from the support layer 22 is attached to and fixedly connected to the electronic component. The hardness of the support layer 22 is greater than that of the adhesive layer 23. This configuration, with two layers, provides a composite film layer. The adhesive layer 23, with its lower hardness, is fixedly connected to the lead frame 1 via hot pressing. The support layer 22, with its higher hardness, supports the electronic component and is less prone to breakage, ensuring the safety of the electronic device. Furthermore, the superposition of the support layer 22 and the adhesive layer 23 gives the composite film layer a certain thickness, resulting in good breakdown strength.

[0035] In this embodiment, both the support layer 22 and the adhesive layer 23 are made of epoxy resin, filler, and curing agent. The curing agent causes the epoxy resin to undergo a cross-linking and curing reaction, forming a network-like three-dimensional polymer. The curing agent can be, but is not limited to, aromatic polyamines, boron trifluoride, etc. The filler is silicon oxide or alumina. The filler is mainly used to reduce the coefficient of thermal expansion of the composite film, improve its thermal conductivity and mechanical strength, so that the composite film can transfer and dissipate the heat generated by the electronic components, and the composite film is not easily damaged, ensuring the reliability of the electronic devices. During the cross-linking and curing process of the epoxy resin, epoxy resin polymers with different hardness can be obtained by adjusting the amount of curing agent added, controlling the curing reaction time, or changing the curing reaction process conditions.

[0036] In a preferred embodiment, the curing rate of the epoxy resin in the support layer 22 is δ1, where δ1 is greater than 95%, and the curing rate of the epoxy resin in the adhesive layer 23 is δ2, where δ2 is greater than 30% and less than 80%. With this configuration, the support layer 22, with its higher curing rate, will only soften slightly when heated, and the pressure from the electronic components will not damage it; the adhesive layer 23, with its lower curing rate, will soften upon heating and possesses a certain degree of adhesion, enabling it to be fixedly connected to the electronic components.

[0037] It should be noted that the support layer 22 is formed by coating the substrate 21 with epoxy resin after degassing treatment, and then bonding the support layer 22 to the substrate 21 using a vacuum hot pressing process. The vacuum hot pressing process involves evacuating the equipment and applying pressure and heat to the substrate 21 and the epoxy resin coating on it, thus bonding the support layer 22 and the substrate 21 together. Using vacuum hot pressing prevents airborne gases or moisture from entering the support layer 22, thereby avoiding the formation of bubbles on the surface of the support layer 22, which would affect the insulation performance of the product. Finally, the layer 23 and the support layer 22 are bonded together by the adhesive properties of the epoxy resin through hot pressing.

[0038] In this embodiment, a protective film 24 is provided on the side of the adhesive layer 23 away from the support layer 22, and the protective film 24 is detachably connected to the adhesive layer 23. This arrangement prevents impurities or foreign objects in the outside air from falling onto the surface of the adhesive layer 23. If these impurities or foreign objects are conductive, they will affect the reliability of the electronic device. When the electronic component is connected to the heat dissipation device 2, the protective film 24 is separated from the adhesive layer 23, and the electronic component is connected to the surface of the adhesive layer 23.

[0039] Specifically, an adhesive layer is provided on the side of the protective film 24 near the adhesive layer 23, so that the protective film 24 is adhered to the surface of the adhesive layer 23. The adhesive layer is made of adhesive, and the protective film 24 may be, but is not limited to, a plastic film. When the protective film 24 is detached from the adhesive layer 23, the adhesive layer and the protective film 24 detach together from the adhesive layer 23.

[0040] The following description, in conjunction with the above embodiments, details the heat dissipation device. In this embodiment, the heat dissipation device 2 includes a substrate 21, a support layer 22, an adhesive layer 23, and a protective film 24 sequentially disposed on the upper surface of the substrate 21. Both the support layer 22 and the adhesive layer 23 are made of epoxy resin, a curing agent, and a filler. The filler is silicon oxide or alumina. The curing agent undergoes a cross-linking reaction with the epoxy resin. By using unequal amounts of curing agent, support layers 22 and 23 with different curing rates are obtained. The curing rate of the epoxy resin in the support layer 22 is greater than 95%, and the curing rate of the epoxy resin in the adhesive layer 23 is greater than 30% and less than 80%. The substrate 21 is made of ceramic. The substrate 21 and the support layer 22 are connected together by vacuum hot pressing. The support layer 22 and the adhesive layer 23 are connected by the adhesive of epoxy resin and by hot pressing. The protective film 24 is attached to the surface of the adhesive layer 23 via an adhesive layer.

[0041] With this setup, the protective film 24 can be peeled off the surface of the adhesive layer 23, allowing electronic components to be attached to the surface of the adhesive layer 23. The heat generated by the electronic components is then dissipated through the heat dissipation device 2. The substrate 21 of the heat dissipation device 2 is made of ceramic material. Ceramic has the characteristics of good insulation, thermal conductivity, high temperature resistance, chemical corrosion resistance, and high strength. It also has good surface flatness, ensuring the reliability of electronic devices and reducing the surface failure rate of electronic devices.

[0042] This invention also provides an electronic device, please refer to... Figure 2 The system includes the heat dissipation device 2 and electronic components as described in the above embodiments. The heat dissipation device 2 is used to dissipate the heat generated by the electronic components. In this configuration, the substrate 21 of the heat dissipation device 2 is made of ceramic material. Ceramic has good insulation and thermal conductivity, is resistant to chemical corrosion, and has high strength, ensuring the electrical safety performance of the electronic components. Ceramic does not oxidize and is not easily scratched, has low warpage, and can prevent molding compound from overflowing onto the surface of the substrate 21 during the encapsulation process. The heat dissipation device 2 dissipates heat, enabling the electronic components to operate normally and reliably, improving the safety factor of the electronic components, and reducing the appearance failure rate of the electronic components. The derivation process of this beneficial effect is largely similar to the derivation process of the beneficial effects brought by the heat dissipation device 2, so it will not be repeated here.

[0043] In this embodiment, the electronic component includes a lead frame 1 and a semiconductor device 3. The lead frame 1 includes a frame body 11 and a base island 12. The frame body 11 surrounds the outer periphery of the base island 12, and the base island 12 is connected to the frame body 11. The electronic component and the heat dissipation device 2 are respectively disposed on both sides of the base island 12. With this arrangement, the heat generated by the electronic component can be transferred to the heat dissipation device 2 more quickly, so that the heat dissipation device 2 can dissipate the heat.

[0044] It should be noted that in this embodiment, the electronic device is an IPM module. The IPM module includes a heat dissipation device 2, a lead frame 1, and a semiconductor chip disposed on the lead frame 1. The lead frame 1 is connected to the bonding layer 23 of the heat dissipation device 2 through a hot pressing process. The semiconductor chip is an IGBT (Insulated Gate Bipolar Transistor) chip. The IGBT chip generates a large amount of heat when it is working, which is dissipated through the heat dissipation device 2.

[0045] In a preferred embodiment, the base island 12 includes a connection portion 121 connected to the pins of the semiconductor device 3. The surface of the connection portion 121 is coated with a silver plating. The semiconductor device 3 is disposed on the base island 12, and the pins of the semiconductor device 3 are connected to the connection portion 121 by soldering gold wires. Since gold and silver have good adhesion, plating silver on the surface of the connection portion 121 can firmly solder the semiconductor device 3 to the lead frame 1. At the same time, silver has good conductivity, which can increase the conductivity between the semiconductor chip and the lead frame 1.

[0046] To prevent the copper lead frame 1 from oxidizing, a corrosion-resistant layer is provided on the surface of the lead frame 1. Preferably, the corrosion-resistant layer is made of nickel, which is typically plated on other metal surfaces to prevent rusting. Moreover, nickel plating on the surface of the lead frame 1 facilitates the soldering of the semiconductor chip onto the base island 12.

[0047] In a preferred embodiment, a stepped structure is formed at the connection between the base island 12 and the frame body 11, and the plane where the base island 12 is located is between the planes where the heat dissipation device 2 and the frame body 11 are located. Specifically, as shown... Figure 3 As shown, the height of the base island 12 is lower than the height of the frame body 11. The heat dissipation device 2 is located on the lower surface of the base island 12, and the semiconductor device 3 is connected to the upper surface of the base island 12 by silver paste or solder. Both the base island 12 and the heat dissipation device 2 are located below the plane of the frame body 11. The aforementioned step structure at the base island 12 position of the lead frame 1 increases the creepage distance between the pins of the semiconductor device 3 and the heat dissipation device 2, resulting in higher safety.

[0048] The following description, in conjunction with the above embodiments, details the electronic device. In this embodiment, the electronic device includes a heat dissipation device 2, a lead frame 1, and a semiconductor chip. The lead frame 1 includes a frame body 11 and a base island 12. The heat dissipation device 2 and the semiconductor chip are respectively disposed on both sides of the base island 12. The base island 12 includes a connection portion 121 connected to the pins of the semiconductor chip. The surface of the connection portion 121 is coated with a silver plating layer. The surface of the lead frame 1, excluding the connection portion 121, is coated with a corrosion-resistant layer made of nickel. A stepped structure is formed at the connection between the frame body 11 and the base island 12. The plane of the base island 12 is located between the planes of the heat dissipation device 2 and the frame body 11. The heat dissipation device 2 consists of a substrate 21 and a support layer 22, an adhesive layer 23, and a protective film 24 sequentially disposed on the upper surface of the substrate 21. The substrate 21 is made of ceramic.

[0049] With this configuration, the heat dissipation device 2 has good heat dissipation effect, and the ceramic has good insulation properties. The heat dissipation device 2 makes the electronic device more reliable. Furthermore, the substrate 21 of the heat dissipation device 2 has stable chemical properties, high strength, and high surface flatness, which can reduce the appearance failure rate of the electronic device.

[0050] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the content not described in detail in some embodiments can be referred to the same or similar content in other embodiments. The multiple solutions provided by the present invention contain their own basic solutions, are independent of each other, and do not restrict each other, but they can also be combined with each other without conflict to achieve multiple effects.

[0051] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An electronic device, characterized in that, It includes a heat dissipation device (2) and electronic components. The heat dissipation device (2) is used to dissipate the heat generated by the electronic components. The electronic components include a lead frame (1) and a semiconductor device (3). The lead frame (1) includes a frame body (11) and a base island (12) connected to the frame body (11). The semiconductor device (3) and the heat dissipation device (2) are respectively disposed on both sides of the base island (12). The base island (12) includes a connection portion (121) connected to the pin of the semiconductor device (3), and the surface of the connection portion (121) is provided with a plating layer, the plating layer being made of silver; The heat dissipation device includes a substrate (21) and a composite film layer laminated on the surface of the substrate (21). The side of the composite film layer away from the substrate (21) is used to attach and fix electronic components. The composite film layer is made of insulating material, and the substrate (21) is made of ceramic. The composite film layer includes a support layer (22) composited on the surface of the substrate (21) and an adhesive layer (23) composited on the side of the support layer (22) away from the substrate (21). The side of the adhesive layer (23) away from the support layer (22) is used to attach and fix electronic components. The hardness of the support layer (22) is greater than that of the adhesive layer (23). The materials of the support layer (22) and the adhesive layer (23) both include epoxy resin, filler and curing agent, and the filler is silicon oxide or aluminum oxide; The curing rate of the epoxy resin in the support layer (22) is δ1, where δ1 > 95%; the curing rate of the epoxy resin in the adhesive layer (23) is δ2, where 30% < δ2 < 80%. The support layer (22) is coated onto the substrate (21) after degassing epoxy resin, and then the support layer (22) is bonded to the substrate (21) by vacuum hot pressing. Then the layer (23) and the support layer (22) are bonded together by the adhesive properties of epoxy resin and hot pressing. The adhesive layer (23) has a protective film (24) on the side away from the support layer (22), and the protective film (24) is detachably connected to the adhesive layer (23).

2. The electronic device as described in claim 1, characterized in that, The protective film (24) is provided with an adhesive layer so that the protective film (24) is connected to the adhesive layer (23).

3. The electronic device as described in claim 1, characterized in that, The surface of the lead frame (1) is provided with a corrosion-resistant layer to prevent oxidation of the lead frame (1).

4. The electronic device as described in claim 3, characterized in that, The corrosion-resistant layer is made of nickel.

5. The electronic device as described in claim 3, characterized in that, The base island (12) forms a stepped structure at the connection with the frame body (11), and the plane where the base island (12) is located is between the plane where the heat dissipation device (2) and the frame body (11) are located.

6. The electronic device as claimed in claim 1, characterized in that, The electronic device is an IPM module.

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