Power module and electronic device equipped with same
The power module design stabilizes the heat dissipation substrate using residual portions and controlled ejector pins to prevent adhesive overflow, ensuring proper attachment and enhancing the packaging effect and reliability.
Patent Information
- Application Number
- JP2024519347
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2023-06-26
- Filing Date
- 2023-10-30
- Publication Date
- 2025-08-21
- Estimated Expiration
- 2043-10-30
AI Technical Summary
The packaging process of power modules can result in warping and adhesive overflow on the heat dissipation substrate due to incomplete attachment and resin impact, affecting the adhesion and performance of the module.
The power module design includes a packaging body with residual portions on its surface to stabilize the heat dissipation substrate during resin injection, using ejector pins to control the substrate's position and prevent adhesive overflow, ensuring tight attachment to the mold without interfering with power chips.
This design stabilizes the heat dissipation substrate, prevents adhesive overflow, and ensures proper adhesion, enhancing the packaging effect and reliability of the power module by maintaining chip functionality and improving assembly accuracy.
Smart Images

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Abstract
Description
[Technical Field]
[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority from Chinese patent application No. 202211442177.8 filed on November 17, 2022, Chinese patent application No. 202310495887.5 filed on April 28, 2023, and Chinese patent application No. 202321635269.8 filed on June 26, 2023, the entire disclosures of which are incorporated herein by reference.
[0002] The present disclosure relates to the field of electronic equipment technology, and more particularly to a power module and an electronic equipment including the same. [Background technology]
[0003] Intelligent power modules (IPMs) have features such as high current density, low saturation voltage, low driving power, high switching frequency, high functionality integration, and high reliability, and can be widely used in many fields such as electronics, automobiles, railway transportation, industrial equipment, new energy, and smart grids. Power modules usually package the power chip and control chip in resin to achieve high integration. Summary of the Invention [Means for solving the problem]
[0004] In one aspect, a power module is provided. The power module includes a packaging body, a heat dissipation substrate provided within the packaging body, and multiple power chips. The packaging body has first and second surfaces facing each other along the thickness direction of the power module, and includes one or more remaining portions located on the first surface. The heat dissipation substrate has third and fourth surfaces facing each other along the thickness direction of the power module. The heat dissipation substrate includes a conductive layer, and the surface of the conductive layer closest to the first surface is the third surface, and the fourth surface is flush with the second surface, so that the fourth surface is exposed from the packaging body. Multiple power chips are provided on the conductive layer and spaced apart along the length direction of the power module. The orthogonal projections of the edges of the one or more remaining portions on the conductive layer and the orthogonal projections of the edges of the power chips on the conductive layer are offset from each other.
[0005] In another aspect, an electronic device including the power module is provided. [Brief explanation of the drawings]
[0006] [Figure 1] FIG. 1 is a structural diagram of a power module according to a related art. [Figure 2] FIG. 1 is a structural diagram of a power module according to some embodiments of the present disclosure. [Figure 3] FIG. 2 is another block diagram of a power module according to some embodiments of the present disclosure. [Figure 4] FIG. 2 is another block diagram of a power module according to some embodiments of the present disclosure. [Figure 5] FIG. 1 is a plan view of a power module according to some embodiments of the present disclosure. [Figure 6] FIG. 6 is an enlarged view of an N region in the power module shown in FIG. [Figure 7] FIG. 1 is a front package effect view of a power module according to some embodiments of the present disclosure. [Figure 8] FIG. 1 is a perspective view of a power module according to some embodiments of the present disclosure. [Figure 9]FIG. 9 is an enlarged view of a region M in the power module shown in FIG. [Figure 10] FIG. 2 is another plan view of a power module in accordance with some embodiments of the present disclosure. [Figure 11] FIG. 2 is another plan view of a power module in accordance with some embodiments of the present disclosure. [Figure 12] FIG. 2 is another plan view of a power module in accordance with some embodiments of the present disclosure. [Figure 13] FIG. 2 is another plan view of a power module in accordance with some embodiments of the present disclosure. [Figure 14] FIG. 1 is a backside package effect diagram of a power module according to some embodiments of the present disclosure. [Figure 15] FIG. 1 is a perspective view of a power module according to some embodiments of the present disclosure. [Figure 16] 1A-1C are schematic diagrams of a packaging process for a power module according to some embodiments of the present disclosure. [Figure 17] 1A-1C are schematic diagrams of a packaging process for a power module according to some embodiments of the present disclosure. [Figure 18] 1A-1C are schematic diagrams of a packaging process for a power module according to some embodiments of the present disclosure. [Figure 19] FIG. 2 is a schematic diagram of an annular recess on a first surface of a power module according to some embodiments of the present disclosure. [Figure 20] FIG. 2 is another block diagram of a power module according to some embodiments of the present disclosure. [Figure 21] FIG. 21 is a schematic diagram of a package mold corresponding to the power module shown in FIG. 20. [Figure 22] FIG. 1 is a block diagram of an electronic device according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION
[0007] Hereinafter, several embodiments of the present disclosure will be clearly and completely described with reference to the drawings. Of course, the embodiments described herein are only a part of the embodiments of the present disclosure, and are not all of the embodiments. All other embodiments that can be conceived by those skilled in the art based on the embodiments in the present disclosure shall fall within the scope of protection of the present disclosure.
[0008] Unless the context indicates otherwise, in this specification and claims, the term "comprise" and other forms thereof, such as the third-person singular "comprises" and the present participle form "comprising," should be interpreted in an open, inclusive sense, i.e., "including, but not limited to." In the description, the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific example," "some examples," and the like, are intended to indicate that a particular feature, structure, material, or characteristic associated with this embodiment or examples is included in at least one embodiment or example of the present disclosure. General references to the above terms do not necessarily refer to the same embodiment or example. Furthermore, a described particular feature, structure, material, or characteristic may be included in any one or more embodiments or examples in any appropriate manner.
[0009] Hereinafter, the terms "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying the relative importance or quantity of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In describing the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.
[0010] In describing some embodiments, the term "connected" and its derivatives may be used. For example, in describing some embodiments, the term "connected" may be used to indicate that two or more elements are in direct physical or electrical contact with each other.
[0011] "A and / or B" includes three combinations: A only, B only, and a combination of A and B.
[0012] As used herein, "about," "approximately," or "approximate" includes the stated value and the mean within an acceptable range of deviation of the specified value, where the acceptable range of deviation is determined by one of ordinary skill in the art considering the measurement and the error associated with measuring the specified quantity (i.e., limitations of the measurement system).
[0013] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized illustrative drawings. In the drawings, thicknesses of layers and regions are exaggerated for clarity. The exemplary embodiments of the present disclosure are not limited to the shapes of regions illustrated herein and should be construed to include deviations in shape due to manufacturing or otherwise. For example, an etching region shown as a rectangle typically has curved features. Thus, the regions shown in the drawings are exemplary in nature, and their shapes are not intended to represent the actual shape of the regions of the facility and are not intended to limit the scope of the exemplary embodiments.
[0014] Electronic devices typically incorporate a power module to achieve their functions. In the related art, the packaging body of a power module is typically obtained by packaging a driver chip and a power chip using an injection molding process. FIG. 1 shows a structural diagram of a power module. The power module 10 includes a heat dissipation substrate 100, a power chip 200 mounted on the heat dissipation substrate 100, a drive frame 300, a driver chip 400 mounted on the drive frame 300, and a packaging body 500 configured to package the heat dissipation substrate 100, the power chip 200, the drive frame 300, and the driver chip 400.
[0015] During the injection molding process, the heat dissipation substrate 100 on which the power chip 200 is mounted and the drive frame 300 on which the drive chip 400 is mounted are fixed in the cavity of a packaging mold, resin is injected into the cavity through the resin injection port of the packaging mold, and the mold is released after the resin has hardened, thereby completing the packaging of the power module. However, during the resin injection process, the free end of the heat dissipation substrate 100 may not be completely attached to the surface of the packaging mold, which may cause the heat dissipation substrate 100 to warp when heated. In addition, the flowing resin may impact the heat dissipation substrate 100, affecting the adhesion between the heat dissipation substrate 100 and the packaging mold, and the flowing resin may overflow onto the back surface of the heat dissipation substrate 100 (the surface away from the power chip 200). As a result, adhesive overflows onto the back surface of the substrate, affecting the performance of the power module 10.
[0016] Based on this, an embodiment of the present disclosure provides a power module, which may be an intelligent power module (IPM). As shown in FIGS. 2 to 5, the power module 10 includes a heat dissipation substrate 100, a plurality of power chips 200 mounted on the heat dissipation substrate 100, and a packaging body 500 mounted on the heat dissipation substrate 100 and the power chips 200. The heat dissipation substrate 100 includes a conductive layer 110 configured to mount the plurality of power chips 200 thereon, i.e., the conductive layer 110 is used as a pad for the power chips 200. The plurality of power chips 200 are mounted on the conductive layer 110 and spaced apart along the longitudinal direction X of the power module 10.
[0017] The packaging body 500 has a first surface 501 and a second surface 502 that face each other in the thickness direction Z of the power module 10. The first surface 501 is located on the side of the power chip 200 that is farther from the heat dissipation substrate 100, and may be called the top surface of the packaging body 500. The second surface 502 is located on the side of the heat dissipation substrate 100 that is farther from the power chip 200, and may be called the bottom surface of the packaging body 500.
[0018] The heat dissipation substrate 100 is located inside the packaging body 500 and has a third surface 101 and a fourth surface 102 that face each other in the thickness direction Z of the power module 10. The third surface 101 is the surface close to the first surface 501 of the heat dissipation substrate 100, and the fourth surface 102 is the surface close to the second surface 502 of the heat dissipation substrate 100. The fourth surface 102 is flush with the second surface 502, and therefore the fourth surface 102 is exposed from the second surface 502 (e.g., the bottom surface) of the packaging body 500. Here, the surface of the conductive layer 110 that is close to the first surface 501 is the third surface 101 of the heat dissipation substrate 100. In other words, the conductive layer 110 is the film layer that is closest to the first surface 501 of the heat dissipation substrate 100 (e.g., the uppermost layer).
[0019] It is understood that since the area of the fourth surface 102 of the heat dissipation substrate 100 is smaller than the area of the second surface 502 of the packaging body 500, when the fourth surface 102 is flush with the second surface 502, the fourth surface 102 occupies only a portion of the second surface 502.
[0020] In describing the configuration of the power module 10, reference will be made to the longitudinal direction X, width direction Y, and thickness direction Z of the power module 10. Here, the thickness direction Z of the power module 10 refers to the direction perpendicular to the plane on which the heat dissipation substrate 100 is located, the longitudinal direction X and width direction Y of the power module 10 are both directions parallel to the plane on which the heat dissipation substrate 100 is located, and the longitudinal direction X of the power module 10 refers to the arrangement direction of multiple pads configured to accommodate multiple power chips 200, and the width direction Y of the power module 10 refers to the extension direction of any of the pads.
[0021] 7 to 13, in order to avoid the problem of adhesive overflowing onto the rear surface of the heat dissipation substrate 100 during the packaging process of the power module 10, one or more residual portions 510 are provided on the first surface 501 of the packaging body 500, and the orthogonal projection of the edge of the residual portion 510 on the conductive layer 110 is offset from the orthogonal projection of the edge of the power chip 200 on the conductive layer 110. It should be understood that the residual portion 510 refers to a depression left on the surface of the packaging body 500 by the ejector pins of the packaging mold after the packaging of the power module 10 is completed.
[0022] For example, FIG. 16 is a schematic diagram of the ejector pins of the package module pressing against the heat dissipation substrate during the injection molding process, FIG. 17 is a schematic diagram of the ejector pins starting to reset during the injection molding process, and FIG. 18 is a schematic diagram of the ejector pins completely reset during the injection molding process. As shown in FIGS. 16 to 18, when packaging the main structure of the power module 10, the ejector pins 810 of the package mold press against the heat dissipation substrate 100 from above (the side where the power chip 200 is provided) through an ejector pin plate and a sleeve. The position of the heat dissipation substrate 100 can be stabilized during the process of injecting resin into the cavity 820 of the package mold. By controlling the ejector pins 810 to start resetting when the resin is almost completely hardened, and then completely removing the package mold after packaging is completed, the heat dissipation substrate 100 can be controlled to adhere closely to the surface of the package mold throughout the entire packaging process. As can be seen from this, the ejector pins 810 of the package mold may be expandable, so that when the resin is injected, the ejector pins 810 expand the sleeve to fix the heat dissipation substrate 100, and when the resin filling is completed and pressure holding begins, the ejector pins 810 contract to complete the entire plastic packaging process. In this way, the ejector pins 810 expand and contract within the space defined by the sleeve, which is advantageous for improving the accuracy of the up and down movement of the ejector pins 810.
[0023] When the ejector pin 810 is used to fix the heat dissipation board 100, the ejector pin 810 is fixed by the bottom plate through the ejector pin plate and sleeve, and power is supplied from the oil circuit so as to push out the ejector pin 810. After the oil circuit power is cut off, the ejector pin 810 is reset by the return spring or reverse oil circuit action.
[0024] Because the reset positions of the ejector pin and the sleeve are closer to the heat dissipation substrate 100 than the cavity surface of the packaging mold, two interlocking annular recesses (such as circular annular recesses) are finally formed on the first surface 501 of the packaging body 500 to prevent resin from filling inside the sleeve. Here, because the reset position of the ejector pin 810 is closer to the heat dissipation substrate 100 than the reset position of the sleeve, as shown in Figures 9 and 19, the annular recess finally formed on the first surface 501 of the packaging body 500 is a stepped hole 512 formed by the ejector pin 810 and the sleeve, with the edge of the sleeve corresponding to the outer circle of the annular recess (i.e., the edge of the recess 511 corresponding to the sleeve), the edge of the ejector pin corresponding to the inner circle of the annular recess (i.e., the edge of the remaining portion 510), and the depth of the remaining portion 510 being greater than the depth of the recess 511 corresponding to the sleeve.
[0025] In this way, the ejector pins 810 can apply pressure to the heat-dissipating substrate 100 during the resin filling process, so that the heat-dissipating substrate 100 is not easily tilted by the impact of the flowing resin, thereby stabilizing the position of the heat-dissipating substrate 100 and preventing the injected resin from spilling onto the rear surface of the heat-dissipating substrate 100. When the ejector pins 810 are removed, the resin has hardened, so the position of the heat-dissipating substrate 100 can be stabilized. This ensures that the heat-dissipating substrate 100 is firmly attached to the bottom of the packaging mold and prevents the adhesive from spilling onto the rear surface of the heat-dissipating substrate 100.
[0026] In the power module 10 provided according to the embodiment of the present invention, the packaging body 500 is formed by hardening a resin injected into a cavity of a packaging mold. During the packaging process of the power module 10, the ejector pins of the packaging mold press the top surface of the heat dissipation substrate 100, thereby allowing the heat dissipation substrate 100 to be tightly attached to the bottom surface of the packaging mold without tilting during the resin injection process. This prevents the resin from overflowing to the back side of the heat dissipation substrate 100, which is advantageous for packaging the power module 10. The power module 10 formed based on this has one or more remaining portions 510 on the first surface 501 of the packaging body 500, and the fourth surface 102 of the heat dissipation substrate 100, which is remote from the power chip 200, is flush with the second surface 502 (bottom surface), so that the fourth surface 102 of the heat dissipation substrate 100 is exposed to the bottom surface of the packaging body 500, thereby ensuring a good packaging effect of the power module 10. Furthermore, when the ejector pins press against the heat dissipation substrate 100, the positions of the ejector pins are controlled to be offset from the positions of the power chips 200 on the heat dissipation substrate 100, thereby realizing that the orthogonal projection of the remaining portion 510 on the conductive layer 110 of the heat dissipation substrate 100 is offset from the orthogonal projection of the edge of the power chips 200 on the conductive layer 110. This prevents the ejector pins from coming into contact with the power chips 200 during the packaging process, preventing interference between the ejector pins and the power chips 200, thereby avoiding damage to the power chips 200 and ensuring the normal operation of the power chips 200, and ultimately ensuring the normal use of the power module 10.
[0027] For convenience of explanation, as shown in FIGS. 5 and 10 to 15, both sides of the power module 10 along the width direction Y may be referred to as the drive side 10A and the power side 10B, respectively. In some embodiments, the power module 10 includes a heat dissipation substrate 100, a plurality of power chips 200 provided on the heat dissipation substrate 100, a plurality of power pins 600 connected to the heat dissipation substrate 100, a drive frame 300, at least one drive chip 400 on the drive frame 300, a plurality of drive pins 700 connected to the drive frame 300, and a packaging body 500. Here, the plurality of power pins 600 are spaced apart along the length direction of the power module 10, with one end connected to the heat dissipation substrate 100 and the other end extending outside the packaging body 500. The plurality of drive pins 700 are spaced apart along the length direction X of the power module 10, with one end connected to the drive frame 300 and the other end extending outside the packaging body 500. The multiple drive pins 700 and the multiple power pins 600 are located on both sides of the power module 10 in the width direction Y. The side on which the multiple drive pins 700 are located is called the drive side 10A, and the side on which the multiple power pins 600 are located is called the drive side 10B.
[0028] The driver chip 400 is electrically connected to the power chip 200 and is configured to drive the power chip 200 to operate in order to realize the functions of the power module 10. Illustratively, the driver chip 400 includes a low-voltage driver chip and a high-voltage driver chip, and some of the plurality of driver pins 700 are electrically connected to the low-voltage driver chip and other parts are electrically connected to the high-voltage driver chip. When the power module 10 is operating, the plurality of driver pins 700 and the plurality of power pins 600 are connected to an external controller, thereby realizing electrical connection between the internal circuit of the power module 10 and an external circuit and realizing normal use of the power module 10.
[0029] The heat dissipation substrate 100, the power chip 200, the driving frame 300, and the driving chip 400 are all disposed within a packaging body 500. The packaging body 500 is a protective shell formed, for example, of a packaging resin, and is configured to protect the internal structure, thereby improving the reliability of the assembly between the driving frame 300 and the heat dissipation substrate 100 and providing good protection for the driving chip 400 and the power chip 200, thereby improving the performance and reliability of the power module 10.
[0030] In an embodiment of the present disclosure, as shown in FIGS. 5 and 10 to 13, the conductive layer 110 may include a plurality of base islands, such as a first base island 111, a second base island 112, a third base island 113, and a fourth base island 114, spaced apart along the longitudinal direction X of the power module 10. A plurality of power chips 200 are provided on the plurality of base islands. The number of power chips 200 provided on each base island may be designed according to actual needs.
[0031] The areas of the first base island 111, the second base island 112, the third base island 113, and the fourth base island 114 may be different, and the number of power chips 200 provided on each base island may also be different. For example, the areas of the first base island 111, the second base island 112, and the third base island 113 are all smaller than the area of the fourth base island 114, i.e., the fourth base island 114 has the largest area. In this case, one power chip 200, such as a low-voltage power chip, is provided on the first base island 111, the second base island 112, and the third base island 113, and three power chips 200, such as a high-voltage power chip, are provided on the fourth base island 114, with the high-voltage power chip and the low-voltage power chip all being provided closer to the driving side 10A. In this way, multiple high-voltage power chips are integrated on the fourth base island 114, saving space and improving the compactness of the power module 10. Furthermore, the low-voltage power chips and high-voltage power chips are spaced apart to not only meet the power requirements of various circuits, but also avoid mutual interference between different power domains, thereby ensuring the stability and reliability of the power chips.
[0032] For example, the power chip 200 may include a MOS (metal-oxide-semiconductor) chip, an IGBT (insulated gate bipolar transistor) chip, an FRD (fast recovery diode) chip, two chips consisting of an IGBT chip and an FRD chip, or an RC-IGBT (reverse-conducting insulated gate bipolar transistor) chip in which an FRD chip is built into an IGBT chip. This allows at least one of the IGBT chip, the FRD chip, and the RC-IGBT chip to be selected and used as needed, improving convenience.
[0033] As can be seen from the above embodiments, one or more remaining portions 510 are provided on the first surface 501 of the packaging body 500. Considering that the remaining portions 510 are depressions left on the surface of the packaging body 500 by ejector pins during the packaging process, and the ejector pins are provided to prevent adhesive from overflowing on the back surface of the heat dissipation substrate 100, the number and distribution of the ejector pins are related to the dimensions of the heat dissipation substrate 100.
[0034] 10 and 11 , the dimension of the heat dissipation substrate 100 along the length direction X of the power module 10 is denoted by L, and the number of the one or more remaining portions 510 is denoted by n. When L≦40 mm, 2≦n≦4, where L and n are positive integers. That is, when the length of the heat dissipation substrate 100 is 40 mm or less, the number of remaining portions 510 provided is 2 to 4. In this case, these remaining portions 510 include at least two remaining portions 510 located at both ends along the length direction X of the power module 10, and along the thickness direction Z of the power module 10, these two remaining portions 510 respectively correspond to two of the multiple base islands located at both ends along the length direction X of the power module 10.
[0035] The correspondence between the remaining portion 510 and the base island means that, in the thickness direction Z of the power module 10, at least a portion of the orthogonal projection of the remaining portion 510 onto the conductive layer 110 of the heat dissipation substrate 100 is located on the base island, i.e., the orthogonal projection of the remaining portion 510 onto the conductive layer 110 overlaps with the base island.
[0036] For example, the conductive layer 110 of the heat dissipation substrate 100 includes a first base island 111, a second base island 112, a third base island 113, and a fourth base island 114 that are sequentially spaced apart along the longitudinal direction X of the power module 10. The length L of the heat dissipation substrate 100 is 40 μm or less. Two, three, or four remaining portions 510 are provided on the first surface 501 of the packaging body 500 at intervals along the longitudinal direction X of the power module 10. Of these remaining portions 510, the orthogonal projections of two remaining portions 510 located at both ends of the remaining portion 510 on the conductive layer 110 overlap the first base island 111 and the fourth base island 114, respectively.
[0037] In this way, when the dimension L of the heat dissipation substrate 100 along the longitudinal direction X of the power module 10 does not exceed 40 mm, the heat dissipation substrate 100 may be fixed using two to four ejector pins during the packaging process, in which case two to four corresponding remaining portions 510 are formed on the first surface 501 of the packaging body 500. Because the dimension of the heat dissipation substrate 100 is relatively small, of the multiple base islands, two base islands located at both ends along the longitudinal direction X of the power module 10 correspond to one remaining portion 510, respectively. In other words, during the packaging process, the two base islands located at both ends are pressed by the corresponding ejector pins, so that the small-sized heat dissipation substrate 100 can be more closely attached to the surface of the packaging mold, thereby preventing the adhesive from overflowing on the back surface of the heat dissipation substrate 100, ensuring the packaging effect of the power module 10, and advantageously improving the reliability of the power module 10.
[0038] In some examples, as shown in FIG. 10 , when L≦25 mm, n=2. That is, when the length of the heat dissipation substrate 100 is 25 mm or less, the number of remaining portions 510 provided is two. The orthogonal projections of the two remaining portions 510 on the conductive layer 110 overlap two of the base islands located at both ends (e.g., the first base island 111 and the fourth base island 114) among the multiple base islands. During the packaging process, for example, an ejector pin presses the first base island 111 and the fourth base island 114.
[0039] Exemplarily, when the dimensions of the heat dissipation substrate 100 are 25×12 mm or less (for example, when the maximum dimensions of the packaging body 500 are 35.6 mm×18.8 mm and the dimensions of the heat dissipation substrate 100 are 22.7 mm×9.15 mm), the heat dissipation substrate 100 is fixed using the two-point fixing method (that is, using two protruding pins), and these two protruding pins are pressed against the non-fixed ends of the first base island 111 and the fourth base island 114 (located at the end of the driving side 10A). For example, they may be pressed against two apex angles located on the driving side 10A of the conductive layer 110.
[0040] In this case, only the two base islands located at both ends are fixed, so that the heat dissipation substrate with dimensions L of 25 mm or less is well adhered to the surface of the packaging mold, and the packaging speed of the power module 10 is further improved.
[0041] Based on this, when the minimum distance between two adjacent power chips 200 is B and the maximum cross-sectional dimension of the remaining portion 510 is C, B and C satisfy B < C + 0.8 mm. Exemplarily, the minimum distance between the power chip 200 provided on the first base island 111 and the power chip 200 provided on the second base island 112 is B. The shape of the remaining portion 510 is an annular shape, the diameter of its outer circle is C, and B < C + 0.8 mm.
[0042] When B = C + 0.8 mm, the distance B between two adjacent power chips 200 can control the distance between the edge of the end of the protruding pin and the power chip 200 within a safe range during packaging. In other words, when no protruding pin is provided between two adjacent power chips 200, B < C + 0.8 mm can be satisfied, that is, the distance between two adjacent power chips 200 becomes smaller. According to such a configuration, it can also be applied to the heat dissipation substrate 100 with a small dimension in the length direction X of the power module 10, which is advantageous for realizing the miniaturization of the power module 10.
[0043] Furthermore, the maximum cross-sectional dimension C of the remaining portion 510 satisfies C = 1.2 mm, and the minimum distance B between two adjacent power chips 200 may satisfy B < 2 mm. For example, when the end face of the protruding pin 810 is circular and the diameter C of the protruding pin 810 is 1.2 mm, the minimum distance B between two adjacent power chips 200 in the length direction X of the power module 10 is less than 2 mm. With such an arrangement, the distance between two adjacent power chips 200 can be reduced, and the dimension along the length direction X of the power module 10 can be reduced.
[0044] In another example, as shown in FIG. 11, when 25 mm < L ≤ 32 mm, n = 3. That is, when the length of the heat dissipation substrate 100 is greater than 25 mm and less than or equal to 32 mm, the number of remaining portions 510 provided is three. Among the three remaining portions 510, the orthographic projection on the conductive layer 110 of the remaining portion 510 located in the middle along the length direction X of the power module 10 overlaps with two adjacent base islands among the plurality of base islands (for example, the second base island 112 and the third base island 113, or the third base island 113 and the fourth base island 114) at the same time, and the orthographic projections on the conductive layers 110 of the two remaining portions 510 located at both ends along the length direction X of the power module 10 overlap with the two base islands located at both ends among the plurality of base islands (for example, the first base island 111 and the fourth base island 114). During the packaging process, the protruding pins press, for example, the first base island 111, the fourth base island 114, and at least one of the middle base islands.
[0045] For example, if the dimensions of the heat dissipation substrate 100 are 25mm x 12mm to 32mm x 15mm (for example, if the maximum dimensions of the packaging body 500 are 38mm x 24mm and the dimensions of the heat dissipation substrate 100 are 30.2mm x 14.2mm), the heat dissipation substrate 100 can be fixed using a three-point fixing method (i.e., using three ejector pins), and these three ejector pins can be pressed against two vertices and a central position of the non-fixed end of the heat dissipation substrate 100, with one of the ejector pins being pressed against a central position of the edge located on the driving side 10A of the heat dissipation substrate 100 corresponding to two adjacent base islands to fix the two base islands simultaneously, and the remaining two ejector pins can be pressed against two vertices located on the driving side 10A of the heat dissipation substrate 100 to fix both ends of the heat dissipation substrate 100.
[0046] In this case, by fixing the two base islands and the conductive layer 110 located at both ends at intermediate positions along the longitudinal direction X of the power module 10, the heat dissipation substrate 100 having a dimension L of more than 25 mm and not more than 32 mm can be firmly attached to the surface of the packaging mold. The centers of the three remaining portions 510 may also be aligned on the same line. In this way, when the three ejector pins are pressed against the heat dissipation substrate 100 simultaneously, the force applied to the non-fixed end of the heat dissipation substrate 100 can be kept uniform. This prevents deformation of the heat dissipation substrate 100 due to stress generated during the resin flow process, further improving adhesion between the heat dissipation substrate 100 and the packaging mold.
[0047] Furthermore, in some examples, when 32 mm < L ≤ 40 mm, n = 4. That is, when the length of the heat dissipation substrate 100 is greater than 32 mm and less than or equal to 40 mm, the number of the provided remaining portions 510 is 4. Among these 4 remaining portions 510, the orthographic projections of the 2 remaining portions 510 located in the middle along the length direction X of the power module 10 on the conductive layer 110 overlap with the 2 base islands located in the middle among the plurality of base islands (for example, the second base island 112 and the third base island 113) respectively, and the orthographic projections of the 2 remaining portions 510 located at both ends along the length direction X of the power module 10 on the conductive layer 110 overlap with the 2 base islands located at both ends among the plurality of base islands (for example, the first base island 111 and the fourth base island 114) respectively. During the packaging process, the protruding pins may press the first base island 111, the second base island 112, the third base island 113, and the fourth base island 114.
[0048] Exemplarily, when the dimensions of the heat dissipation substrate 100 are between 32 mm × 15 mm and 40 mm × 16 mm, the heat dissipation substrate 100 is fixed by using the four-point fixing method (that is, by using four protruding pins), and these four protruding pins are pressed against two vertex angles at the non-fixed ends and two positions at the central part of the heat dissipation substrate 100. Among them, two of the protruding pins are pressed against two vertices located on the driving side 10A of the heat dissipation substrate 100 to fix the base islands located at both ends, and the remaining two protruding pins may be pressed against the edges located on the driving side 10A of the two base islands located in the middle of the heat substrate 100 to fix the base islands located in the middle.
[0049] In this case, by fixing each base island, the heat dissipation substrate 100 with a dimension L greater than 32 mm and less than or equal to 40 mm can be well bonded to the surface of the packaging mold, and the packaging speed of the power module 10 can be further improved.
[0050] In another embodiment, as shown in Figures 12 and 13, the dimension of the heat dissipation substrate 100 along the length direction X of the power module 10 is L, and the number of one or more remaining portions 510 is n. If L > 40 mm, n > 4, where L and n are positive integers. That is, if the length of the heat dissipation substrate 100 is longer than 40 mm, the number of remaining portions 510 provided is greater than four. In this case, each base island corresponds to at least one remaining portion 510 along the thickness direction Z of the power module 10.
[0051] It is understood that "each base island corresponds to at least one remaining portion 510" means that, for any base island, the orthogonal projection of at least one remaining portion 510 on the conductive layer 110 of the heat dissipation substrate 100 overlaps with this base island. The number of remaining portions 510 corresponding to each base island may be the same or different.
[0052] For example, the conductive layer 110 of the heat dissipation substrate 100 includes a first base island 111, a second base island 112, a third base island 113, and a fourth base island 114 that are spaced apart in order along the longitudinal direction X of the heat dissipation substrate 100, and the area of the fourth base island 114 is larger than the areas of the other base islands. The length L of the heat dissipation substrate 100 is greater than 40 m. The first surface 501 of the packaging body 500 is provided with five, six, or more remaining portions 510 that are spaced apart along the longitudinal direction X of the power module 10. Of these residual portions 510, the orthogonal projection of at least one residual portion 510 on the conductive layer 110 overlaps with the first base island 111, the orthogonal projection of at least one residual portion 510 on the conductive layer 110 overlaps with the second base island 111, the orthogonal projection of at least one residual portion 510 on the conductive layer 110 overlaps with the third base island 113, and the orthogonal projection of at least two residual portions 510 on the conductive layer 110 overlaps with the fourth base island 114.
[0053] Thus, if the dimension L of the heat dissipation substrate 100 along the longitudinal direction X of the power module 10 is greater than 40 mm, the heat dissipation substrate 100 may be fixed with five or more ejector pins during the packaging process, in which case two or more corresponding remaining portions 510 are formed on the first surface 501 of the encapsulant 500. Because the dimension of the heat dissipation substrate 100 is relatively large, each base island corresponds to at least one remaining portion 510, i.e., each base island is pressed by at least one corresponding ejector pin during the packaging process, which can more effectively bond the large-sized heat dissipation substrate 100 to the surface of the packaging mold, thereby preventing the adhesive from overflowing on the back surface of the heat dissipation substrate 100 and ensuring the packaging effect of the power module 10, which is advantageous for improving the reliability of the power module 10.
[0054] 12 , when L>40 mm, n=5. That is, when the length of the heat dissipation substrate 100 is greater than 40 mm, the number of remaining portions 510 provided is five. Of these five remaining portions 510, the orthogonal projections of three remaining portions 510 on the conductive layer 110 overlap the first base island 111, the second base island 112, and the third base island 113, respectively, and the orthogonal projections of the remaining two remaining portions 510 on the conductive layer 110 overlap the fourth base island 114.
[0055] For example, when the dimensions of the heat dissipation substrate 100 are 40 mm × 16 mm or more (for example, the maximum dimensions of the packaging body 500 are 52.5 mm × 31 mm and the dimensions of the heat dissipation substrate 100 are 40.9 mm × 17.3 mm), five ejector pins may be used to press against three positions, one at each of the two apex corners and the center of the non-fixed end of the heat dissipation substrate 100. One of the ejector pins may be pressed against an edge close to the apex corner located on the driving side 10A of the first base island 111, another ejector pin may be pressed against an edge close to the apex corner located on the driving side 10A of the second base island 112, another ejector pin may be pressed against an edge close to the apex corner located on the driving side 10A of the third base island 113, and the remaining two ejector pins may be pressed against the center of the edge located on the driving side 10A of the fourth base island 114.
[0056] During the packaging process, the ejector pins press against the first base island 111, the second base island 112, the third base island 113, and the fourth base island 114, and because the area of the fourth base island 114 is larger than those of the first base island, the second base island 112, and the third base island 113, the number of ejector pins pressed against the fourth base island 114 is also greater than that of the other base islands. In this case, by pressing each base island and pressing the base island with a larger area at multiple points, the large-sized heat dissipation substrate 100 can be more closely attached to the surface of the packaging mold.
[0057] 13, when L>40 mm, n>5. That is, when the length of the heat dissipation substrate 100 is greater than 40 mm, the number of remaining portions 510 provided is greater than five. Of these residual portions 510, the orthogonal projection of one residual portion 510 onto the conductive layer 110 overlaps the edge of the first base island 111 away from the second base island 112, the orthogonal projection of one residual portion 510 onto the conductive layer 110 overlaps the adjacent edges of the first base island 111 and the second base island 112, the orthogonal projection of one residual portion 510 onto the conductive layer 110 overlaps the adjacent edges of the second base island 112 and the third base island 113, the orthogonal projection of one residual portion 510 onto the conductive layer 110 overlaps the adjacent edges of the third base island 113 and the fourth base island 114, and the orthogonal projection of the remaining residual portion 510 onto the conductive layer 110 overlaps the fourth base island 114.
[0058] For example, if the dimensions of the heat dissipation substrate 100 are 40 mm x 16 mm or more (e.g., the maximum dimensions of the packaging body 500 are 52.5 mm x 31 mm and the dimensions of the heat dissipation substrate 100 are 40.9 mm x 17.3 mm), five or more, for example seven, ejector pins may be used to press the heat dissipation substrate 100 at multiple positions in the middle between the non-fixed end and the fixed end. One ejector pin may be pressed at the center of the edge of the first base island 111 away from the second base island 112, one ejector pin may be pressed at the center of the edge close to each other between the first base island 111 and the second base island 112, one ejector pin may be pressed at the center of the edge close to each other between the second base island 112 and the third base island 113, one ejector pin may be pressed at the center of the edge close to each other between the third base island 113 and the fourth base island 114, one ejector pin may be pressed at the center of the edge of the fourth base island 114 away from the third base island 113, and the remaining two ejector pins may be pressed at intermediate positions on the fourth base island 114.
[0059] During the packaging process, the ejector pins are pressed at the center of the heat dissipation substrate 100 in the width direction Y, at positions between any adjacent base islands among the first base island 111, the second base island 112, the third base island 113, and the fourth base island 114, at the edge of the first base island 111 away from the fourth base island 114, and against the fourth base island 114. Because the area of the fourth base island 114 is larger than the areas of the first base island 111, the second base island 112, and the third base island 113, the number of ejector pins pressed against the fourth base island 114 is also larger than the number of ejector pins pressed against the other base islands. In this case, by pressing the center of the edges of multiple base islands and pressing the base islands with larger areas at multiple points, the large-sized heat dissipation substrate 100 can be more closely attached to the surface of the packaging mold.
[0060] 7 to 12, when the number n of remaining portions 510 provided on the first surface 501 of the packaging body 500 is 5 or less (n≦5), the orthogonal projections of the n remaining portions 510 on the conductive layer 110 overlap with the edges of the base islands located on the driving side 10A. As shown in FIG. 13, when the number n of remaining portions 510 provided on the first surface 501 of the packaging body 500 is greater than 5 (n>5), the orthogonal projections of the n remaining portions 510 on the conductive layer 110 are located at the centers of the base islands along the width direction Y of the power module 10. This arrangement can prevent warping of the large heat dissipation substrate 100 at the center along the width direction Y of the power module 10, can more stably fix the heat dissipation substrate 100, and can prevent overflow of adhesive on the back surface of the heat dissipation substrate 100.
[0061] 7 to 11, when the number n of remaining portions 510 on the first surface 501 of the packaging body 500 is 5 or less (n≦5), the orthogonal projections of the centers of the two remaining portions 510 on the conductive layer 110 overlap with the vertices at the two corners of the driving side 10A of the conductive layer 110. This not only ensures that the ejector pins can stably press the conductive layer 110 during the packaging process, but also minimizes the area occupied by the ejector pins on the base island, thereby increasing the area on the base island where the power chips 200 can be arranged. It should be understood that this method of arranging the remaining portions 510 is applicable to heat dissipation substrates 100 of any size, and the smaller the size of the heat dissipation substrate 100, the more obvious the advantages of this arrangement.
[0062] 7 to 10 , two remaining portions 510 are provided on the first surface 501 of the packaging body 500, and the orthogonal projections of the centers of the two remaining portions 510 on the conductive layer 110 overlap with vertices located at two corners on the drive surface 10A side of the conductive layer 110. If the outer ring of the remaining portions 510 is circular, for example, the orthogonal projection of the center of one remaining portion 510 on the conductive layer 110 overlaps with a vertex located on the drive side 10A side of the first base island 111 and away from the fourth base island 114, and the orthogonal projection of the center of the other remaining portion 510 on the conductive layer 110 overlaps with a vertex located on the drive surface 10A side of the fourth base island 114 and away from the first base island 111.
[0063] In this way, during the packaging process, both ends of the conductive layer 110 along the longitudinal direction X of the power module 10 are pressed by the ejector pins, making it difficult for the heat dissipation substrate 100 to shift in a position close to the first base island 111 and close to the fourth base island 114, ensuring that the fourth surface 102 of the heat dissipation substrate 100 and the second surface 502 of the packaging body 500 are on the same plane, and better preventing the adhesive from overflowing on the back surface of the heat dissipation substrate 100.
[0064] As can be seen from the above-described embodiments, the size of the heat dissipation substrate 100 varies depending on the dimensions of the power module 10. By designing the number n of remaining portions 510 corresponding to each base island (i.e., the number of ejector pins corresponding to each base island) and the distribution positions of the remaining portions 510 (i.e., the positions where the ejector pins are pressed against the base island) based on the dimension L of the heat dissipation substrate 100 along the longitudinal direction X of the power module 10, it is possible to accurately solve the problem of bonding the heat dissipation substrate 100 to the packaging mold for power modules 10 of different dimensions, thereby preventing overflow of adhesive on the back surface of the heat dissipation substrate 100 and achieving a good packaging effect. In addition, it is possible to reduce the manufacturing process of removing overflowing adhesive from the front surface of the heat dissipation substrate 100, which is advantageous for improving production efficiency.
[0065] In some embodiments, as shown in Figures 5 and 6, the minimum distance A between the orthogonal projection on the conductive layer 110 of the power chip 200 among the multiple power chips 200 that is closest to the remaining portion 510 and the orthogonal projection on the conductive layer 110 of the edge of this remaining portion 510 satisfies A > 0.45 mm.
[0066] For example, one residual portion 510 is formed on the first surface 501 of the packaging body 500 at a position corresponding to the first base island 111, located on the driving side 10A and away from the apex angle of the fourth base island 114, and a power chip 200 close to this residual portion 510 is provided on the first base island 111, and the minimum distance between the upper left vertex of this power chip 200 (see Figure 5) and the edge of the orthogonal projection of this residual portion 510 on the conductive layer 110 is A, and A > 0.45 mm.
[0067] If the minimum distance A between the power chip 200 closest to the remaining portion 510 among the multiple power chips 200 and this remaining portion 510 is less than 0.45 mm, the distance between the orthogonal projection of the remaining portion 510 on the conductive layer 110 and the power chip 200 is small. That is, the distance between the edge of the end face of the ejector pin and the power chip 200 during the packaging process is small. In this case, if the ejector pin is misaligned, the ejector pin is likely to come into contact with the power chip 200, which may result in the ejector pin crushing the power chip 200. Therefore, in the embodiment of the present disclosure, the minimum distance A between the power chip 200 closest to the remaining portion 510 and the edge of the orthogonal projection of this remaining portion 510 on the conductive layer 110 is set to satisfy A>0.45 mm, so that when the end of the ejector pin comes into contact with the conductive layer 110, the distance between the edge of the ejector pin and the power chip 200 can be controlled within a safe range, so that contact between the ejector pin and the power chip 200 can be prevented, and the risk of the ejector pin crushing the power chip 200 can be avoided.
[0068] 14 and 15, a plurality of release portions 520 are provided on the second surface 502 of the packaging body 500. Exemplarily, the release portions 520 may be blind holes, which are depressions left on the second surface 502 of the packaging body 500 during the demolding process. By providing a plurality of release portions 520, the force acting on the packaging body 500 during the demolding process can be dispersed, and damage or deformation of the packaging body 500 can be prevented.
[0069] In some examples, the multiple release portions 520 may include multiple first release portions 521 and multiple second release portions 522. The multiple first release portions 521 and the multiple second release portions 522 are located on both edges of the second surface 502 along the width direction Y of the power module 10, respectively, and the multiple first release portions 521 and the multiple second release portions 522 are arranged at intervals along the length direction X of the power module 10. Exemplarily, the multiple release portions 520 may include three first release portions 521 spaced apart along the length direction X of the power module 10 and three second release portions 522 spaced apart along the length direction X of the power module 10. The second release portion 521 is located on the drive side 10A of the power module 10, and the second release portion 522 is located on the power side 10B of the power module 10.
[0070] In this way, after the packaging of the power module 10 is completed, the packaging body 500 can be released from the mold by extending the release pins provided corresponding to the positions of the first release portion 521 and the second release portion 522, which is advantageous for releasing the power module 10. Furthermore, by providing a plurality of first release portions 521 and a plurality of second release portions 522, the release pins are provided corresponding to a plurality of positions in the longitudinal direction X and a plurality of positions in the width direction Y of the corresponding power module 10 of the packaging body 500, and the stability of the release of the packaging body 500 can be improved.
[0071] In another example, the plurality of release portions 520 may further include a plurality of third release portions 523 and a plurality of fourth release portions 524. Demolding Section 523 and multiple fourth Demolding The portion 524 is a first portion having a plurality of first grooves arranged along the width direction Y of the power module 10. Demolding Part 521 and multiple second Demolding The plurality of third release portions 523 are located between the first release portion 521 and the second release portion 522. The packaging body 500 has a first side surface 503 and a second side surface 504 facing each other along the length direction X of the power module 10. The plurality of third release portions 523 are located between the heat dissipation substrate 100 and the first side surface 503 of the packaging body 500, and the plurality of fourth release portions 524 are located between the heat dissipation substrate 100 and the second side surface 504 of the packaging body 500. Exemplarily, the plurality of release portions 520 may include two third release portions 523 and two fourth release portions 523 located between the first release portion 521 and the second release portion 522 in the width direction Y of the power module 10. The two third release portions 523 are located between the first base island 111 and the first side surface 503 of the packaging body 500 along the length direction X of the power module 10 and are spaced apart along the width direction Y of the power module 10. The two fourth release portions 524 are located between the fourth base island 114 and the second side surface 504 of the packaging body 500 along the longitudinal direction X of the power module 10 and are spaced apart along the width direction Y of the power module 10.
[0072] In this way, after the packaging of the power module 10 is completed, the packaging body 500 can be removed from the mold by extending the release pins provided corresponding to the positions of the third release portion 523 and the fourth release portion 524, which is advantageous for releasing the power module 10. Furthermore, by providing the first release portion 521 and the second release portion 522 on the edges of the packaging body 500 and the third release portion 523 and the fourth release portion 524 in the center of the packaging body 500, corresponding release pins are provided on the edges and the center of the packaging body 500, which further improves the stability of the release of the packaging body 500.
[0073] 14 and 15, in some embodiments, the plurality of third release portions 523 and the plurality of fourth release portions 524 are symmetrical in a plane with respect to the center of the packaging body 500 along the width direction Y of the power module 10, i.e., the plurality of third release portions 523 and the plurality of fourth release portions 524 are symmetrical in the up-down direction in FIG. 17. And / or, the plurality of third release portions 523 and the plurality of fourth release portions 524 are symmetrical in a plane with respect to the center of the packaging body 500 along the length direction X of the power module 10, i.e., the plurality of third release portions 523 and the plurality of fourth release portions 524 are symmetrical in the left-right direction in FIG.
[0074] This arrangement ensures that uniform stress is applied to the power module 10 during the demolding process, allowing for smooth demolding of the power module 10. Furthermore, the symmetrically arranged third demolding portion 523 and fourth demolding portion 524 are also advantageous for processing.
[0075] It is understood that a plurality of release portions 520, which are depressions that remain on the first surface 501 of the packaging body 500 during the demolding process, are also provided on the first surface 501 of the packaging body 500. The plurality of release portions 520 are uniformly provided on the first surface 501, thereby ensuring that the force applied to the packaging body 500 is uniform during the demolding process and preventing damage or deformation of the packaging body 500.
[0076] As can be seen from the above, the multiple first release portions 521 and the multiple second release portions 522 are away from the central axis ab along the width direction Y of the power module 10, and the multiple third release portions 522 and the multiple fourth release portions 524 are close to the central axis ab along the width direction Y of the power module 10.
[0077] In some embodiments, as shown in Figures 7, 8, 14, and 15, the packaging body 500 may further include two notches 530. The two notches 530 may be located at both ends of the packaging body 500 along the length direction X of the power module 10 to facilitate fixing of the packaging body 500. Exemplarily, the notches 530 may be circular or U-shaped notches to facilitate assembling the power module 10 with other components. The centers of the two notches 530 may be located on the central axis ab along the width direction Y of the power module 10.
[0078] In addition, the number of each of the third release portions 523 and the fourth release portions 524 is two. Along the width direction Y of the power module 10, the two third release portions 523 are located on both sides of the notch 530 close to the first side surface 503 of the packaging body 500, and the two fourth release portions 524 are located on both sides of the notch 530 close to the second side surface 504 of the packaging body 500.
[0079] For example, when the centers of the two notches 530 are located on the central axis ab along the width direction Y of the power module 10, the two third release portions 523 are located on both sides of the central axis ab and are symmetrical with respect to the central axis, and the two fourth release portions 524 are also located on both sides of the central axis ab and are symmetrical with respect to the central axis ab. This can prevent deformation and damage to the packaging body 500 during the demolding process and can extend the service life of the packaging mold.
[0080] In some embodiments, as shown in FIG. 14, the intersection of the connecting line between the two third release portions 523 and the central axis ab is located at the center of the notch 530 close to the first side surface 503 and the center of the notch 530. Axis a The connecting line between the two fourth release portions 524 and the center Axis a The intersection point with b is the center of the notch 530 close to the second side surface 504 and the intersection point with the center of the notch 530. Axis a It is located between the intersection of b.
[0081] Taking the power module 10 shown in FIG. 14 as an example, the orthogonal projections of the centers of the two notches 530 on the surface where the packaging body 500 is located are respectively points a and b (the connecting line between them is the center line). Axis a b), the centers of the two third release portions 523 are points c and d, respectively, and point a is closer to points c and d than point b, and the notch 530 and the center Axis a The intersection of b is point e, and the connecting line between point c and point d is the center Axis a If the intersection of points a and b is point f, point f is located between points a and e. Based on this, in the longitudinal direction X of the power module 10, the two third release portions 523 are closer to the center of the packaging body 500 than the center a of the notch 530 on the left end. Similarly, in the longitudinal direction X of the power module 10, the two fourth release portions 524 are closer to the center of the packaging body 500 than the center b of the notch 530 on the right end.
[0082] In this way, the third release portion 523 and the fourth release portion 524 are closer to the center of the packaging body 500 than the notches 530 located at both ends of the packaging body 500, which can improve the release stability of the power module 10 and avoid damage to the packaging body 500 during the demolding process, thereby extending the service life of the packaging mold.
[0083] As can be seen from the above embodiment, the heat dissipation substrate 100 has a third surface 101 and a fourth surface 102, and the fourth surface 102 of the heat dissipation substrate 100 is flush with the second surface 502 of the packaging body 500. As shown in Figures 2 to 4, the surface of the conductive layer 110 on which the power chip 200 is provided is the third surface 101. In addition to the conductive layer 110, the heat dissipation substrate 100 may further include other film layers.
[0084] 3 , the heat dissipation substrate 100 may further include a ceramic layer 120 and a heat dissipation layer 130. Along the thickness direction Z of the power module 10, the conductive layer 110 and the heat dissipation layer 130 are located on both sides of the ceramic layer 120. Here, the surface of the heat dissipation layer 130 away from the conductive layer 110 is flush with the second surface 502 of the packaging body 500, i.e., the surface of the heat dissipation layer 130 away from the conductive layer 110 is the fourth surface 102.
[0085] For example, the conductive layer 110 may be made of a metal material with excellent conductivity such as copper, the heat dissipation layer 130 may be made of a metal material with excellent heat dissipation such as copper, and the ceramic layer 120 may use an insulating resin material to prevent current from escaping. Based on this, the conductive layer 110, the ceramic layer 120, and the heat dissipation layer 130 may be a copper layer, a ceramic layer, and a copper layer, and the three may form a DBC (Direct Bond Copper) structure.
[0086] In this way, the heat generated by the power chip 200 during operation is dissipated in a timely manner through the conductive layer 110, the ceramic layer 120 and the heat dissipation layer 130, thereby achieving heat dissipation of the power module 10, ensuring the reliability of the power module 10 and improving the usage performance of the power module 10.
[0087] 4 , the heat dissipation substrate 100 may further include a ceramic layer 120 located on the side away from the first surface 501 of the conductive layer 110. The surface of the ceramic layer 120 away from the conductive layer 110 is flush with the second surface 502 of the packaging body 500, i.e., the surface of the ceramic layer 120 away from the conductive layer 110 is the fourth surface 102.
[0088] For example, the conductive layer 110 may be made of a metal material with excellent conductivity, such as copper, and the ceramic layer 120 may be made of an insulating material with excellent heat dissipation properties. Based on this, the conductive layer 110 and the ceramic layer 120 may form a single-sided copper-clad ceramic plate, and the ceramic layer 120 has both the functions of insulation and heat dissipation.
[0089] In this way, the heat generated by the power chip 200 during operation is dissipated in a timely manner through the conductive layer 110 and the ceramic layer 120, thereby achieving heat dissipation of the power module 10, ensuring the reliability of the power chip 200, and improving the usage performance of the power module 10.
[0090] In some embodiments, as shown in FIG. 2 , the conductive layer 110 and the power pins 600 have an integral structure. That is, the conductive layer 110 includes a portion located inside the packaging body 500 and a portion extending outside the packaging body 500. The portion of the conductive layer 110 located inside the packaging body 500 can be used as a pad for the power chip 200, and the portion of the conductive layer 110 extending outside the packaging body 500 can be used as the power pins 600. Based on this, the heat dissipation substrate 100 further includes an insulating resin heat dissipation sheet located on a side away from the first surface 501 of the conductive layer 110. The insulating resin heat dissipation sheet is configured such that a heat dissipation sheet 150 is connected to one side of the insulating resin sheet 140. The other side of the insulating resin sheet 140 is connected to the conductive layer 110 configured as a pad for the power chip 200, and the surface of the heat dissipation sheet 150 away from the conductive layer 110 is flush with the second surface 502 of the packaging body 500. For example, the heat dissipation sheet 150 may be a copper sheet, and the insulating resin heat dissipation sheet is usually an insulating resin copper sheet.
[0091] 14 and 15 , the packaging body 500 may further include a first step portion 540 and a second step portion 550 that are recessed inward from both sides of the packaging body 500 in the width direction Y of the packaging body 500. The first step portion 540 and the second step portion 550 are disposed opposite each other. Here, the recessed first step portion 540 and the second step portion 550 mean that the first step portion 540 and the second step portion 550 are recessed toward the inside of the packaging body 500.
[0092] The first step portion 540 is located on the side of the lead-out portion of the drive pins 700 that is closer to the second surface 502 of the packaging body 500, and is recessed in a direction in which the drive pins 700 face the power pins 600. The first step portion 540 has a first step surface 541 and a first connection surface 542 that is connected between the first step surface 541 and the second surface 502.
[0093] The second step portion 550 is located on the side of the lead-out portion of the multiple power pins 600 that is closer to the second surface 502 of the packaging body 500, and is recessed in a direction in which the multiple power pins 600 face the multiple drive pins 700. The second step portion 550 has a second step surface 551 and a second connection surface 552 that is connected between the second step surface 551 and the second surface 502.
[0094] In this way, by providing the first step portion 540 and the second step portion 550, the space between the heat dissipation substrate 100 and the side surface on the side where the drive pin 700 corresponding to the cavity of the mounting mold is located, and the space between the heat dissipation substrate 100 and the side surface on the side where the power pin 600 is located can be reduced, thereby reducing the amount of resin that accumulates in these two locations during the resin injection process and reducing the risk of burrs being generated due to resin overflowing from the bottom surface of the heat dissipation substrate 100.
[0095] 14 and 15, the plurality of first release portions 521 and the plurality of second release portions 522 may be provided on the first step surface 541 of the first step portion 540 and the second step surface 551 of the second step portion 550, respectively, and the plurality of third release portions 523 and the plurality of fourth release portions 524 may be provided on the second surface 502. With this configuration, the packaging body 500 can be stably released from the mold.
[0096] In some embodiments, the heat dissipation substrate 100 may adopt the aforementioned DBC structure or single-sided copper-clad structure. In this case, as shown in FIG. 20 , the packaging body 500 may further include a resin injection portion 560 located on the side of the packaging body 500 where the power pins 600 are provided. Along the thickness direction Z of the power module 10, a distance H1 from the second step surface 551 of the second step portion 550 to the second surface 502 of the packaging body 500 is smaller than a distance H0 from the resin injection portion 560 to the second surface 502 of the packaging body 500, and the distance H1 from the second step surface 551 of the second step portion 550 to the second surface 502 of the packaging body 500 is smaller than a distance H5 from the surface of the power chip 200 away from the conductive layer 110 to the second surface 502 of the packaging body 500.
[0097] In the process of packaging the main body structure of the power module 10, as shown in Fig. 21, the main body structure of the power module 10 may be placed in a cavity 820 of a packaging mold, and the packaging mold has a resin injection port A, which is injected into the cavity 820 and fills the gap between the main body structure of the power module 10 and the cavity wall of the mold cavity. After the resin is cured, the packaging body 500 in Fig. 20 is formed, and the portion of the packaging body 500 corresponding to the resin injection port A is a resin injection portion 560, and the roughness of the resin injection portion 560 is greater than the roughness of the other portions of the packaging body 500.
[0098] It is understood that the shape of the cavity wall of the packaging mold matches the outer shape of the packaging body 500. As can be seen from this, the cavity 820 of the packaging mold has a first step 821 corresponding to the first step portion 540 of the packaging body 500 and a second step 822 corresponding to the second step portion 550 of the packaging body 500, and the distance H1′ from the step surface of the second step 822 to the bottom surface of the cavity is smaller than the distance from the surface away from the conductive layer 110 of the power chip 200 to the bottom surface of the cavity, and the distance H1′ from the step surface of the second step 822 to the bottom surface of the cavity is smaller than the height H0′ of the resin injection port A (i.e., the distance from the resin injection port A to the bottom surface of the cavity).
[0099] In this manner, when resin is injected into the cavity of the package mold through resin injection port A, the liquid resin first falls onto second step 822. Second step 822 provides a certain buffering effect on the liquid resin, reducing the height at which the resin flows toward heat dissipation substrate 100 and reducing the downward impact force of the resin on heat dissipation substrate 100. Based on this, since the height of second step 822 is smaller than the distance from the top surface of power chip 200 to the bottom surface of the cavity, and the resin flows from lower to higher toward power chip 200, the resin flows more slowly, further reducing the resin pressure and further reducing the impact force of the resin on heat dissipation substrate 100 and power chip 200, preventing adhesive from overflowing on the back surface of heat dissipation substrate 100 and mitigating the problem of misalignment of heat dissipation substrate 100.
[0100] 20, a distance H1 from the second step surface 551 of the second step portion 550 to the second surface 502 of the packaging body 500 along the thickness direction Z of the power module 10 is approximately equal to a distance H2 from the first step surface 541 of the first step portion 540 to the second surface 502 of the packaging body 500, and / or a distance H3 from the second connecting surface 552 of the second step portion 550 to the third side surface 505 of the packaging body 500 near the portion of the power pin 600 extending outward from the packaging body along the width direction Y of the power module 10 is approximately equal to a distance H4 from the first connecting surface 541 of the first step portion 540 to the fourth side surface 506 of the packaging body 500 near the portion of the drive pin 700 extending outward from the packaging body. Such a configuration, in addition to the use of a buffer resin, can simplify the manufacturing process.
[0101] In some embodiments, as shown in FIGS. 15 and 20 , the first step portion 540 may include a first main body portion extending along the length direction X of the power module 10, a first end portion extending along the width direction Y of the power module 10, and a first flow guide portion 545 connected between the first main body portion and the first end portion, and / or the second step portion 550 may include a second main body portion extending along the length direction X of the power module 10, a second end portion extending along the width direction Y of the power module 10, and a second flow guide portion 555 connected between the second main body portion and the second end portion.
[0102] Both the first flow guide portion 545 and the second flow guide portion 555 may be chamfered, rounded, grooved, or have other structures that can achieve resin flow guidance. By providing flow guide portions at the corners of the first step portion 540 and / or the second step portion 550, a component force that guides the resin to the opposite side can be generated to promote the flow of the resin, thereby preventing the resin from stagnating or accumulating at the corners and causing voids in the resin.
[0103] For example, the first step portion 540 may include only one first guide portion 545, or may include two first guide portions 545, each connected between the first end and the first main body portion.
[0104] Also, for example, the second step portion 550 may include only one second flow guide portion 555, or may include two second flow guide portions 555, each second flow guide portion 555 being connected between the second end portion and the second main body portion.
[0105] In addition to forming a flow guide portion at the corner of the first step portion 540 and / or the second step portion 550, a flow guide portion is formed at the corner between two adjacent side surfaces among the first side surface 503, the second side surface 504, the third side surface 505 and the fourth side surface 506 of the packaging body 500.
[0106] As a result, when the liquid resin flows to the corners in the mold cavity corresponding to the flow guides, the flow of the resin is promoted by the flow guides, preventing the formation of resin voids due to the retention or accumulation of resin. Furthermore, by providing the flow guides, the amount of resin retention is reduced, further reducing the risk of burrs occurring due to the resin overflowing from the bottom surface of the heat dissipation substrate 100.
[0107] In one embodiment of the present invention, an electronic device is provided, and at least one power module of the above embodiment is applicable to the electronic device. As shown in Fig. 22, an electronic device 1000 may include a power module 10 and a controller 20 connected to the power module 10.
[0108] For example, the controller 20 may generate a control signal according to a user instruction and transmit the control signal to the power module 10. The power module 10 generates a drive signal according to the control signal and outputs the drive signal to a corresponding element waiting to be driven, thereby realizing a corresponding function.
[0109] The electronic device provided by the embodiment of the present invention has the same technical effects as the power module of the above embodiment included therein, and therefore a repeated description thereof will be omitted here.
[0110] In the description of this disclosure, a first feature being "above" or "below" a second feature may include direct contact between the first and second features, or may include contact between the first and second features through another feature between them, rather than direct contact. A first feature being "above," "above," and "above" a second feature may include the first feature being directly above and diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature.
[0111] In describing this disclosure, orientations or positional relationships indicated by the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc. are orientations or positional relationships indicated based on the drawings and do not indicate or imply that the devices or elements shown have a particular orientation or are required to be configured and operate in a particular orientation, but are merely intended to facilitate and simplify the description of the invention.
[0112] While embodiments of the present disclosure have been illustrated and described, it will be understood that those skilled in the art can make various changes, modifications, substitutions and variations to these embodiments without departing from the principles and scope of the present invention, the scope of which is defined by the claims and their equivalents.
[0113] Those skilled in the art will appreciate that the scope of the present disclosure is not limited to the particular examples described above, and that modifications and substitutions can be made to specific elements of the examples without departing from the spirit of the present application. The scope of the present disclosure is limited by the claims.
Claims
1. A power module, a packaging body having a first surface and a second surface provided opposite to each other along a thickness direction of the power module, and including one or more remaining portions located on the first surface; a heat dissipation substrate provided within the packaging body, having a third surface and a fourth surface provided opposite to each other along a thickness direction of the power module, and including a conductive layer, wherein a surface of the conductive layer close to the first surface is the third surface, and the fourth surface is flush with the second surface, so that the fourth surface is exposed from the packaging body; a plurality of power chips disposed on the conductive layer and spaced apart along a length of the power module; an orthogonal projection of an edge of the one or more remaining portions on the conductive layer and an orthogonal projection of an edge of the power chip on the conductive layer are offset from each other; the power module has two widthwise sides, each of which is a drive side and a power side; the conductive layer includes a plurality of base islands spaced apart along the lengthwise direction of the power module; the power chips are provided on the base islands; and the one or more remaining portions are n remaining portions; when n≦5, orthogonal projections of the n remaining portions on the conductive layer overlap edges of the base islands located on the driving side; when n>5, orthogonal projections of the n remaining portions on the conductive layer are located at central portions of the plurality of base islands along the width direction of the power module. Power module.
2. a minimum distance A between an orthogonal projection on the conductive layer of a power chip among the plurality of power chips that is closest to the remaining portion and an orthogonal projection on the conductive layer of an edge of the remaining portion satisfies A>0.45 mm; The power module according to claim 1 .
3. When the dimension of the heat dissipation substrate along the longitudinal direction of the power module is L, L≦40 mm and 2≦n≦4, where L and n are positive integers, the n remaining portions include at least two remaining portions located at both ends along the length direction of the power module, and the remaining portions located at both ends along the thickness direction of the power module correspond to two base islands located at both ends along the length direction of the power module among the plurality of base islands, respectively.
3. The power module according to claim 1 or 2.
4. When L≦25 mm, n=2, the minimum distance between two adjacent power chips is B, and the maximum cross-sectional dimension of the remaining portion is C, and B and C satisfy B<C+0.8 mm, when 25 mm<L≦32 mm, n=3, and an orthogonal projection of one remaining portion, which is located at the middle along the longitudinal direction of the power module, among the n remaining portions, on the conductive layer simultaneously overlaps two adjacent base islands among the plurality of base islands; when 32 mm<L≦40 mm, n=4, and orthogonal projections of two intermediate remaining portions along the longitudinal direction of the power module, among the n remaining portions, on the conductive layer overlap two intermediate base islands among the plurality of base islands, respectively. The power module according to claim 3 .
5. When the dimension of the heat dissipation substrate along the longitudinal direction of the power module is L, L>40 mm and n>4, where L and n are positive integers; Along the thickness direction of the power module, each base island corresponds to at least one remaining portion.
3. The power module according to claim 1 or 2.
6. n=5, the plurality of base islands include a first base island, a second base island, a third base island, and a fourth base island that are spaced apart sequentially along the longitudinal direction of the power module, and the area of the fourth base island is larger than the area of the first base island, the area of the second base island, and the area of the third base island; orthogonal projections of three of the n remaining portions onto the conductive layer overlap the first base island, the second base island, and the third base island, respectively, and orthogonal projections of the remaining two of the n remaining portions onto the conductive layer overlap the fourth base island. The power module according to claim 5 .
7. n>5, the plurality of base islands include a first base island, a second base island, a third base island, and a fourth base island that are spaced apart sequentially along the longitudinal direction of the power module, and an area of the fourth base island is larger than an area of the first base island, an area of the second base island, and an area of the third base island; of the n residual portions, the orthogonal projection of one residual portion onto the conductive layer overlaps with the edge of the first base island away from the second base island, the orthogonal projections of the other three residual portions onto the conductive layer overlap with the edges of the first base island and the second base island that are close to each other, the edges of the second base island and the third base island that are close to each other, and the edges of the third base island and the fourth base island that are close to each other, respectively, and the orthogonal projections of the remaining residual portions onto the conductive layer overlap with the fourth base island. The power module according to claim 5 .
8. When n≦5, orthogonal projections of centers of two remaining portions located at both ends along the length direction of the power module onto the conductive layer overlap with vertices located at two corners of the driving side of the conductive layer, respectively. The power module according to claim 1 .
9. The packaging body further includes a plurality of release portions located on the second surface, the plurality of release portions comprising: a plurality of first release portions and a plurality of second release portions, each located at both edges of the second surface along the width direction of the power module, the plurality of first release portions being arranged at intervals along the length direction of the power module, and the plurality of second release portions being arranged at intervals along the length direction of the power module; a plurality of third release portions and a plurality of fourth release portions, which are located between the plurality of first release portions and the plurality of second release portions along the width direction of the power module, and the plurality of third release portions are located between the heat dissipation substrate and a first side surface of the packaging body along the length direction of the power module, and the plurality of fourth release portions are located between the heat dissipation substrate and a second side surface of the packaging body, 3. The power module according to claim 1 or 2.
10. the plurality of third release portions are plane-symmetrical with respect to a center of the packaging body along the width direction of the power module, and the plurality of fourth release portions are plane-symmetrical with respect to a center of the packaging body along the width direction of the power module, and / or the plurality of third release portions and the plurality of fourth release portions are planarly symmetrical with respect to a center of the packaging body along the length direction of the power module. The power module according to claim 9.
11. the packaging body further includes two notches, the two notches being located at both ends of the packaging body along the length direction of the power module; the plurality of third release portions are two third release portions, and the two third release portions are located on both sides of a notch close to the first side surface along a width direction of the power module, the plurality of fourth release portions are two fourth release portions, and the two fourth release portions are located on both sides of a notch close to the second side surface along the width direction of the power module; The power module according to claim 10.
12. the centers of the two notches are located on a central axis along a width direction of the power module, an intersection of a connection line between the two third release portions and the central axis is located between a center of the notch close to the first side surface and an intersection of the notch and the central axis, an intersection of a connection line between the two fourth release portions and the central axis is located between a center of a notch close to the second side surface and an intersection of the notch and the central axis; The power module according to claim 11.
13. the heat dissipation substrate further includes a ceramic layer and a heat dissipation layer, the conductive layer and the heat dissipation layer are located on both sides of the ceramic layer along the thickness direction of the power module, and a surface of the heat dissipation layer away from the conductive layer is the fourth surface; or the heat dissipation substrate further includes a ceramic layer located on a side away from the first surface of the conductive layer, and the surface of the ceramic layer away from the conductive layer is a fourth surface.
3. The power module according to claim 1 or 2.
14. a drive frame provided within the packaging body; at least one driver chip disposed on the driver frame and electrically connected to the plurality of power chips; a plurality of drive pins spaced apart along the length of the power module, one end of which is connected to the drive frame and the other end of which extends outside the packaging body; a plurality of power pins spaced apart along the length of the power module, one end connected to the conductive layer and the other end extending outside the packaging body; the plurality of drive pins and the plurality of power pins are located on both sides along a width direction of the power module, 3. The power module according to claim 1 or 2.
15. The packaging body is a second step portion located on a side of the portion of the power pins extending outward from the packaging body that is closer to a second surface of the packaging body, the second step portion being recessed in a direction in which the power pins are directed toward the drive pins, the second step portion having a second step surface and a second connection surface connected between the second step surface and the second surface; a distance from a second step surface of the second step portion to a second surface of the packaging body along a thickness direction of the power module is shorter than a distance from a surface of the power chip away from the conductive layer to the second surface of the packaging body; 15. The power module according to claim 14.
16. the packaging body further includes a first step portion located on a side of the portion of the plurality of drive pins extending outward from the packaging body that is closer to a second surface of the packaging body and recessed in a direction toward the plurality of drive pins, the first step portion having a first step surface and a first connection surface connected between the first step surface and the second surface, The plurality of release portions include: a plurality of first release portions located on the first step surface and arranged at intervals along the length direction of the power module; a plurality of second release portions located on the second step surface and arranged at intervals along the length direction of the power module; a plurality of third release portions and a plurality of fourth release portions located on the second surface, the plurality of third release portions being located between the heat dissipation substrate and a first side surface of the packaging body along a longitudinal direction of the power module, and the plurality of fourth release portions being located between the heat dissipation substrate and a second side surface of the packaging body, 16. The power module according to claim 15.
17. a distance from a second step surface of the second step portion to a second surface of the packaging body 500 along the thickness direction of the power module is approximately equal to a distance from a first step surface of the first step portion to a second surface of the packaging body, and / or a distance from a second connection surface of the second step portion to a third side surface of the packaging body near a portion of the power pin extending outward from the packaging body along the width direction of the power module is approximately equal to a distance from a first connection surface of the first step portion to a fourth side surface of the packaging body near a portion of the drive pin extending outward from the packaging body.
17. The power module of claim 16.
18. The first step portion includes a first flow guide portion located at a corner portion, and / or the second step portion includes a second flow guide portion located at a corner portion.
18. The power module according to claim 17.
19. A power module according to claim 1 or 2, electronic equipment.
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