Power module and electronic device

Abstract

The invention discloses a power module and electronic equipment. The power module comprises a power chip; the driving integrated circuit is electrically connected with the power chip; the heat dissipation substrate is provided with a first surface and a second surface which are oppositely arranged, a first side and a second side which are opposite in the length direction of the heat dissipation substrate, and a third side close to the driving integrated circuit, the power chip is arranged on the first surface of the heat dissipation substrate, and the heat dissipation substrate comprises an insulating layer, a first conductive layer and a second conductive layer, the second conductive layer comprises a main body part and an extension part connected with the main body part, the extension part extends towards the outer side of the insulating layer, and the extension part is arranged on at least one of the first side, the second side and the third side; at least one core-pulling pinhole is formed in the side, opposite to the second face of the heat dissipation substrate, of the packaging resin, the projection, in the thickness direction of the packaging resin, of the core-pulling pinhole is partially overlapped with the corresponding extending part, and the core-pulling pinhole is located on the outer side of the insulating layer.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and more specifically to a power module and an electronic device. Background Art

[0002] The power module for driving the motor includes a power chip and a ceramic substrate. The power chip is arranged on the ceramic substrate. When the power chip is encapsulated by encapsulation resin, the core-pulling needle presses the ceramic substrate to prevent glue overflow. The ceramic substrate usually includes two conductive layers and an insulating layer (such as a ceramic layer) located between the two conductive layers. However, when pressing, the core-pulling needle usually presses on the conductive layer of the ceramic substrate where the power chip is arranged, so that the insulating layer is also subjected to pressing force, which makes the insulating layer of the ceramic substrate easy to break, thereby affecting the yield and reliability of the module. Summary of the invention

[0003] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further described in detail in the Detailed Description of the Invention section. The Summary of the Invention section of this application does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0004] In order to at least partially solve the above problem, according to a first aspect of the present application, a power module is provided, comprising:

[0005] Power chip;

[0006] A driving integrated circuit, the driving integrated circuit is electrically connected to the power chip;

[0007] The heat dissipation substrate has a first surface and a second surface arranged opposite to each other, a first side and a second side arranged opposite to each other in the length direction thereof, and a third side close to the driving integrated circuit, wherein the power chip is arranged on the first surface of the heat dissipation substrate, wherein the heat dissipation substrate comprises:

[0008] an insulating layer, the insulating layer having a first surface and a second surface opposite to the first surface, wherein the insulating layer is at least one of an aluminum nitride ceramic layer or a silicon nitride ceramic layer;

[0009] A first conductive layer is disposed on a first surface of the insulating layer, wherein a surface of the first conductive layer away from the insulating layer constitutes at least a portion of a first surface of the heat dissipation substrate,

[0010] A second conductive layer is disposed on the second surface of the insulating layer, the second conductive layer comprises a main body and an extension portion connected to the main body, the extension portion is extended to the outside of the insulating layer and the first conductive layer, wherein the extension portion is disposed on at least one of the first side, the second side and the third side;

[0011] The encapsulation resin encapsulates the power chip, the heat dissipation substrate and the driver integrated circuit, wherein at least a portion of the second surface of the heat dissipation substrate is exposed from the encapsulation resin.

[0012] Among them, at least one core pulling pinhole is arranged on the side of the packaging resin opposite to the second surface of the heat dissipation substrate, and the projection of the core pulling pinhole in the thickness direction of the packaging resin overlaps with its corresponding extension part and is located outside the insulating layer and the first conductive layer.

[0013] The above technical scheme has the following advantages and beneficial effects: since the spatial position of the core pulling pin hole corresponds to the position of the core pulling needle during packaging, during packaging, the core pulling pin corresponding to the core pulling pin hole partially falls on the extension part and is located on the outside of the insulating layer, so that during packaging, the core pulling pin presses the extension part without exerting force on the insulating layer, thereby avoiding pressing the insulating layer. While avoiding glue overflow on the second side of the ceramic substrate, the rupture of the insulating layer is prevented, thereby ensuring the reliability and yield of the module. Moreover, since the core pulling pin presses the extension part of the second conductive layer, it is not easy to interfere with the power chip on the first conductive layer, which is conducive to arranging a power chip with a larger size on the heat dissipation substrate to improve the product's current capacity and power, and can also be conducive to arranging the power chip close to the edge of the first conductive layer, thereby reducing the inductance.

[0014] Exemplarily, the center of the projection of each core-pulling pin hole in the thickness direction of the encapsulation resin is located on the extension portion.

[0015] The above technical solution has the following advantages and beneficial effects: through such a setting, the center of the core pulling needle is also located on the extension part during packaging, thereby ensuring that the core pulling needle can fully contact the extension part and apply pressure to it, thereby better ensuring that the second side of the heat dissipation substrate and the plastic packaging mold are fitted together, avoiding glue overflow on the second side of the heat dissipation substrate.

[0016] For example, the projection area of ​​each core-pulling pinhole in the thickness direction of the encapsulation resin is set as S, and the overlapping area of ​​the projection of each core-pulling pinhole in the thickness direction of the encapsulation resin and its corresponding extension portion is set as S1, then

[0017] The above technical solution has the following advantages and beneficial effects: through such an arrangement, during packaging, the center of gravity of the core-pulling needle falls on the extension part, which can better achieve the pressing effect and avoid glue overflow on the second side of the heat dissipation substrate.

[0018] Exemplarily, the spacing distance between the projection of the core-pulling pin hole on the extension portion and the insulating layer adjacent thereto is set to A, and then A≥0.3 mm.

[0019] The above technical solution has the following advantages and beneficial effects: the spacing distance A can ensure a safe distance between the core-pulling needle and the insulating layer, avoid pressing the insulating layer, and prevent the insulating layer from cracking while avoiding glue overflow on the second side of the ceramic heat dissipation substrate.

[0020] Exemplarily, the distance between the edge of the extension portion and the edge of the adjacent insulating layer is set to B, and the radius of the projection of each core-pulling pinhole in the thickness direction of the packaging resin is set to R, then B satisfies the following formula: B≥R+0.3.

[0021] The above technical solution has the following advantages and beneficial effects: during packaging, the center of gravity of the core-pulling needle falls on the extension part, which can better achieve the pressing effect and avoid glue overflow on the second side of the heat dissipation substrate.

[0022] Exemplarily, there are multiple power chips, and the multiple power chips are arranged on the heat dissipation substrate at intervals along the length direction, wherein the edges of the multiple power chips close to the driving integrated circuit are flush.

[0023] The above technical solution has the following advantages and beneficial effects: by making the edge of the power chip close to the driver integrated circuit flush, the spacing distance between the power chip and the driver integrated circuit can be reduced as much as possible, which is conducive to reducing the length of the connecting line between the two, thereby reducing the gate inductance and reducing switching losses. Such a setting is also conducive to integrating larger power chips to improve the product's current capacity and power.

[0024] Exemplarily, a distance between an edge of the plurality of power chips close to the driver integrated circuit and an edge of the first conductive layer close to the driver integrated circuit is less than 0.8 mm.

[0025] The above technical solution has the following advantages and beneficial effects: through such a setting, the spacing distance between the power chip and the driver integrated circuit can be reduced as much as possible, which is conducive to reducing the length of the connecting line between the two, thereby reducing the gate inductance and reducing switching losses. Such a setting is also conducive to integrating larger power chips to improve the product's current capacity and power.

[0026] Exemplarily, when the volume of the encapsulation resin is within a first threshold range, an extension portion is provided on both the first side and the second side;

[0027] When the volume of the encapsulation resin is within a second threshold range, providing an extension portion on the third side;

[0028] When the volume of the encapsulation resin is within a third threshold range, an extension portion is provided on the first side, the second side, and the third side.

[0029] The upper limit value of the first threshold range is smaller than the lower limit value of the second threshold range, and the upper limit value of the second threshold range is smaller than the lower limit value of the third threshold range.

[0030] The above technical solution has the following advantages and beneficial effects: by adapting the appropriate heat dissipation substrate type to packages of different sizes, the pressing effect of the core pulling needle can be better achieved, and glue overflow on the second side of the heat dissipation substrate 30 can be avoided.

[0031] Exemplarily, the width of the encapsulation resin in the width direction is set to L1, and the length of the encapsulation resin in the length direction is set to L2, wherein, when the volume of the encapsulation resin is within the first threshold range, 16mm≤L1≤20mm, and 31.5mm≤L2≤36.5mm; when the volume of the encapsulation resin (10) is within the second threshold range, 36mm≤L2≤40mm, and 22mm≤L1≤26mm; when the volume of the encapsulation resin (10) is within the third threshold range, 29mm≤L1≤33mm, and 50mm≤L2≤60mm.

[0032] The above technical solution has the following advantages and beneficial effects: by adapting suitable heat dissipation substrate types to packages of different sizes, the pressing effect of the core pulling needle can be better achieved, and glue overflow on the second side of the heat dissipation substrate can be avoided.

[0033] Exemplarily, an inner groove recessed inward from a side surface of the insulating layer is provided in the insulating layer, and one side of the inner groove is opened to face the second conductive layer.

[0034] The above technical solution has the following advantages and beneficial effects: by providing the inner groove, the creepage distance of the second conductive layer can be increased, thereby improving electrical safety.

[0035] Another aspect of the present application provides an electronic device, which includes the aforementioned power module.

[0036] The above technical solution has the following advantages and beneficial effects: since the electronic device includes the above power module, it has substantially the same advantages as the above power module. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The following drawings of the present application are used as a part of the present application for understanding the present application. The drawings show the embodiments of the present application and their descriptions, which are used to explain the device and principle of the present application.

[0038] Figure 1A A schematic top view of a power module in the related art is shown;

[0039] Figure 1B A schematic diagram showing the positional relationship between the core pulling needle and the ceramic substrate in the related art is shown;

[0040] Figure 1C A schematic diagram showing encapsulation by encapsulation resin is shown;

[0041] Figure 1D A cross-sectional schematic diagram of a power module after packaging in the related art is shown;

[0042] Figure 1E Shows Figure 1D A partial enlarged view of the area surrounded by the circle of encapsulating resin;

[0043] Figure 2 A schematic top view of a power module in an embodiment of the present application is shown;

[0044] Figure 3A A schematic diagram showing some dimensions and directions of the power module in an embodiment of the present application is shown;

[0045] Figure 3B In the embodiment of the present application, Figure 3A An enlarged schematic diagram of a local area of ​​a power module;

[0046] Figure 4 A schematic top view of a power module in an embodiment of the present application is shown;

[0047] Figure 5 Shown along Figure 4 A schematic partial cross-sectional view of the power module obtained along the section line DD;

[0048] Figure 6 In the embodiment of the present application, Figure 5 A partial enlarged schematic diagram of the area surrounded by the circle of encapsulating resin;

[0049] Figure 7 A cross-sectional schematic diagram of a heat dissipation substrate in one embodiment of the present application is shown;

[0050] Fig. 8A A schematic top view of a heat dissipation substrate in one embodiment of the present application is shown;

[0051] Figure 8B A schematic top view of a heat dissipation substrate in another embodiment of the present application is shown;

[0052] Figure 8C A schematic top view of a heat dissipation substrate in yet another embodiment of the present application is shown.

[0053] Fig. 9 A cross-sectional schematic diagram of a heat dissipation substrate in another embodiment of the present application is shown;

[0054] Reference numerals:

[0055] 100. Power module;

[0056] 10. Encapsulation resin; 11. First side; 12. Second side;

[0057] 110, core-pulling pin hole; 111, core-pulling pin

[0058] 20. driving side frame; 21. driving side pad; 22. high voltage driving side pad; 221. high voltage driving integrated circuit; 23. low voltage driving side pad; 231. low voltage driving integrated circuit;

[0059] 24, drive side pin; 241, floating power supply voltage pin; 242, floating power supply ground pin; 243, chip power supply voltage pin; 25, bootstrap chip pad; 251, bootstrap chip;

[0060] 30. Heat dissipation substrate; 31. Power side pad; 32. High-voltage power side pad; 321. High-voltage power side RC-IGBT; 33. Low-voltage power side pad; 331. Low-voltage power side RC-IGBT; 34. Power side pin; 35. Gate pad; 36. Emitter pad; 361. Pin electrical connection solder joint; 262. Pin electrical connection wire.

[0061] 301, first conductive layer; 302, second conductive layer; 3021, extension portion; 3022, main body portion; 303, insulating layer; 3001, first side; 3002, second side; 3031, first surface; 3032, second surface; 311, first side; 312, second side; 313, third side; 3033, inner groove.

[0062] 41. Ceramic layer; 42. Conductive layer. DETAILED DESCRIPTION

[0063] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present application. However, it is apparent to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features well known in the art are not described.

[0064] It should be understood that the present application can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present application to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0065] It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as a second element, component, region, layer or part.

[0066] Spatially relative terms such as "under", "beneath", "below", "under", "above", "above", etc., may be used herein for convenience of description to describe the relationship of one element or feature to other elements or features shown in the figures. It should be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation shown in the figures.

[0067] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "a", "an" and " / the" are also intended to include plural forms, unless the context clearly indicates another way. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0068] Embodiments of the invention are described herein with reference to cross-sectional views as schematic diagrams of ideal embodiments (and intermediate structures) of the present application. Thus, variations in the shapes shown due to, for example, manufacturing techniques and / or tolerances can be expected. Therefore, embodiments of the present application should not be limited to the specific shapes shown herein, but include shape deviations due to, for example, manufacturing. Therefore, what is shown in the figures is schematic in nature, and their shapes are not intended to display the actual shape of the device and are not intended to limit the scope of the present application.

[0069] In order to thoroughly understand the present invention, detailed steps and structures will be presented in the following description to illustrate the technical solution proposed by the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementations.

[0070] like Figures 1A to 1EAs shown, the power module (Intelligent Power Module, referred to as power module) includes a power chip and a heat dissipation substrate. The power chip is arranged on the heat dissipation substrate (also known as a ceramic substrate). When the electronic components of the power module are encapsulated by encapsulating resin, it is necessary to first place the heat dissipation substrate, power chip, drive side frame, drive integrated circuit, etc. that need to be encapsulated in the plastic encapsulation mold, and then inject resin into the mold. The core pulling pin is a retractable ejector pin design. When the resin is filled, the ejector pin extends and presses the conductive layer on the ceramic layer (that is, the conductive layer away from the bottom of the plastic encapsulation mold), so that the ceramic substrate can be close to the plastic encapsulation mold to avoid glue overflow on the back of the ceramic substrate. When the resin filling is completed and the pressure is maintained, the core pulling pin retracts and completes the entire plastic encapsulation process. At this time, the core pulling pin sleeve is transferred to the opposite side of the encapsulation resin and the heat dissipation substrate of the power module, leaving a sleeve hole, and the core pulling pin is transferred to the opposite side of the encapsulation resin and the heat dissipation substrate of the power module to leave a core pulling pin hole, wherein the sleeve hole and the core pulling pin hole are coaxial, and the diameter of the sleeve hole is larger than the diameter of the core pulling pin hole. It is worth mentioning that, in order to facilitate the illustration of the positional relationship between the core pulling needle and the conductive layer, the core pulling needle is illustrated as a rectangular block in some drawings herein, but it should be understood that this should not constitute a limitation on its shape.

[0071] like Figure 1A , Figure 1B to Figure 1C As shown, the core-pulling needle 111 presses the ceramic substrate to prevent glue overflow. The ceramic substrate usually includes two conductive layers and an insulating layer (such as a ceramic layer 41) located between the two conductive layers. However, when pressing, the core-pulling needle usually presses on the conductive layer 42 of the ceramic substrate where the power chip is set, so that the insulating layer is also subjected to pressing force, which makes the insulating layer of the ceramic substrate easy to break, thereby affecting the yield and reliability of the module.

[0072] Below, we will refer to the attached Figures 2 to 9 A power module in an embodiment of the present application is described. In order to mark the dimensions more clearly, the reference numerals of multiple structures are omitted in FIG. 3 . Some of the reference numerals can be referred to in FIG. Figure 2 It is worth mentioning that, under the premise of no conflict, the various technical features in the embodiments of the present application can be combined with each other.

[0073] To solve the above technical problems, Figure 2 and Figure 3A As shown, an embodiment of the present application provides a power module 100, including: a power chip, a driving integrated circuit, a heat dissipation substrate 30 and a packaging resin 10, etc.

[0074] Optionally, the power chip may be an RC-IGBT or an IGBT and a fast recovery diode (FRD) or other suitable types of power chips. In the following, the embodiment of the present application is mainly described by taking the case where the power chip may be an RC-IGBT as an example.

[0075] Among them, the reverse conducting IGBT (RC-IGBT) can be a semiconductor switching element that is basically rectangular, including an IGBT (Insulated Gate Bipolar Transistor) and a freewheeling diode arranged on a semiconductor substrate. Since the separate IGBT chips or freewheeling diodes arranged on different semiconductor substrates respectively include a terminal area and an active area, when the two devices are combined into one chip, the terminal part can be shared, thereby reducing the area of ​​the terminal part. Therefore, the size of the RC-IGBT is usually smaller than the size of the structure in which the IGBT and the freewheeling diode are arranged on different semiconductor substrates. Therefore, when the RC-IGBT is used as the power chip of the power module, the size of the power chip and even the size of the power module can be reduced. The reverse conducting insulated gate bipolar transistor is a single power chip, which can reduce the number of cores on the power module 100 and the number of bonding wires.

[0076] In some embodiments, the RC-IGBT includes a terminal structure, and the terminal structure may adopt a lateral variable doping structure. The above technical solution has the following advantages and beneficial effects: the terminal structure of the RC-IGBT adopts a lateral variable doping structure, which can further reduce the chip area of ​​the RC-IGBT compared to the terminal structure of the field limiting ring or the field limiting ring plus the field plate, thereby facilitating the miniaturization of the module.

[0077] Lateral variable doping refers to the formation of a region with a gradual change in impurity doping concentration in the terminal region of the device through, for example, ion implantation. Usually, ion implantation is performed on the substrate region near the heavily doped main junction to form a lateral variable doping structure. The closer the region is to the main junction, the greater the doping concentration, and the farther the region is, the smaller the doping concentration.

[0078] In some embodiments, the number of RC-IGBTs is multiple, for example, including three high-voltage power-side RC-IGBTs and three low-voltage power-side RC-IGBTs constituting inversion. Specifically, the number of RC-IGBTs can be reasonably set according to actual needs.

[0079] The driver integrated circuit is electrically connected to the RC-IGBT for controlling the RC-IGBT. For example, the driver integrated circuit and the RC-IGBT are electrically connected via an electrical connector such as a wire. The driver integrated circuit controls the RC-IGBT, for example, drives the RC-IGBT to turn it on or off. For example, the driver integrated circuit protects the RC-IGBT when an abnormality occurs (for example, overvoltage protection and / or over-temperature protection and / or electrostatic protection, etc.).

[0080] The number of driver integrated circuits can be reasonably set according to the RC-IGBTs to be driven. For example, the number of driver integrated circuits can be one or more. When the number is multiple, it can include one high-voltage driver integrated circuit and one low-voltage driver integrated circuit, or three high-voltage driver integrated circuits and one low-voltage driver integrated circuit, or other suitable situations. The high-voltage driver integrated circuit drives the high-voltage power side RC-IGBT to turn on or off, while the low-voltage driver integrated circuit drives the low-voltage power side RC-IGBT to turn on or off. Optionally, multiple electronic components, such as transistors, diodes, triodes, resistors or capacitors, can be integrated in the driver integrated circuit.

[0081] The heat dissipation substrate 30 has a first surface and a second surface that are arranged relatively, wherein the RC-IGBT is arranged on the first surface of the heat dissipation substrate 30, for example, the first surface side of the heat dissipation substrate 30 has a power side pad 31, and the RC-IGBT is arranged on the power side pad 31. The RC-IGBT can be supported by the heat dissipation substrate 30, and the heat dissipation substrate 30 has good thermal conductivity, which can improve the heat dissipation effect of the RC-IGBT and improve the reliability of the RC-IGBT. The RC-IGBT can be led out by using the power side pad 31 on the first surface side of the heat dissipation substrate for electrical connection with other components, and the direct electrical connection of the RC-IGBT can be achieved by directly setting the RC-IGBT on the power side pad 31, thereby optimizing the wiring of the power module and making its structure simpler. Optionally, the heat dissipation substrate can be a ceramic substrate with a conductive layer or other suitable types of substrates.

[0082] In order to meet the heat dissipation requirements of power chips with different high current specifications, the areas of heat dissipation substrates corresponding to power chips with different current specifications are also different. In some embodiments, the rated current of the RC-IGBT is defined as I, and the area of ​​the heat dissipation substrate 30 is set as S. Then, when I satisfies the relationship: 26A≤I≤35A, S satisfies the relationship: 161.25mm2≤S≤275mm 2 In other embodiments, when I satisfies the relationship: 45A≤I≤55A, S satisfies the relationship: 350mm 2 ≤S≤550mm 2In some other embodiments, when I satisfies the relationship: 70A≤I≤80A, S satisfies the relationship: 480mm 2 ≤S≤820mm 2 By such an arrangement, the encapsulation resin can satisfy the space requirement of the driving side frame or driving side PCB (printed circuit board) for mounting the driving integrated circuit, and also satisfy the space requirement of the heat dissipation substrate for heat dissipation of the power chip (such as IGBT and FRD, or RC-IGBT).

[0083] The encapsulation resin (10) encapsulates the RC-IGBT, the heat dissipation substrate 30 and the driver integrated circuit. The encapsulation resin is obtained by mold encapsulation. The mold encapsulation can be generated by transfer molding using a thermosetting resin, for example. The encapsulation resin can be an epoxy resin or other resin material suitable for semiconductor module encapsulation. The opposite sides of the encapsulation resin in the width direction are the drive side and the power side, respectively. At least part of the heat dissipation substrate, the power chip such as the RC-IGBT and the driver integrated circuit are encapsulated in the encapsulation resin. In this way, the encapsulation resin can provide physical and electrical protection for at least part of the heat dissipation substrate, the RC-IGBT and the driver integrated circuit to prevent damage to at least part of the heat dissipation substrate, the RC-IGBT and the driver integrated circuit caused by external environmental impact, thereby ensuring the normal operation of the power module 100.

[0084] At present, the relevant technology can only realize packaging of IGBT chips with large current specifications in a large package, which is obviously not conducive to achieving miniaturization of products.

[0085] In the embodiments of the present application, in order to realize the packaging of a power chip with a larger current specification in a smaller packaging resin, for example, to realize the packaging of a power chip with a current specification of 26A≤I≤35A, the relevant dimensions of the packaging resin and the RC-IGBT are optimized. In some embodiments of the present application, Figure 2 and Figure 3A As shown, the width direction of the encapsulation resin (i.e. Figure 3A The width L1 of the encapsulation resin of the power module is set in the length direction (i.e., the width L2 ... Figure 2 If the length of the package (in the length direction shown in FIG) is L2, then L2 is less than or equal to 36.5 mm. By reducing the length and width of the packaging resin, it is beneficial to achieve miniaturization of the product.

[0086] When 26A≤I≤35A, it is a large current specification; the larger the chip current specification, the higher the chip temperature, and the greater the thermal stress on the corresponding chip; for a relatively small package, its heat dissipation is usually limited, resulting in a higher chip temperature and greater thermal stress, which in turn increases the probability of chip failure. Therefore, in some embodiments of the present application, the width L1 of the width direction of the packaging resin is also greater than or equal to 16mm, that is, 16mm≤L1≤20mm, and the length L2 of the length direction of the packaging resin is also greater than or equal to 31.5mm, that is, 31.5mm≤L2≤36.5mm. By keeping the size of the packaging resin within the above range, it can be beneficial to the miniaturization of the product while meeting the requirements of the current specification of 26A≤I≤35A as much as possible, and realizing the packaging of a larger current specification in a relatively small packaging resin, suppressing the problem of higher chip temperature and greater thermal stress due to the small size of the packaging resin, thereby reducing the probability of chip failure.

[0087] When the rated current I of RC-IGBT is less than 26A, the heat dissipation margin of the RC-IGBT chip is large due to the heat dissipation substrate and the package body, and the current specification is relatively small, so the heat generated by the RC-IGBT chip during operation is low, and the temperature will also be low, and the thermal stress of the chip will be small. The problem of failure of the RC-IGBT chip packaged in a relatively small package will hardly occur, so that the chip aspect ratio and ceramic substrate material will not limit the power module and have little impact on chip reliability.

[0088] However, when 26A≤I≤35A, it is a large current specification; the larger the chip current specification, the higher the chip temperature, and the greater the thermal stress on the corresponding chip; and in the above-mentioned small package (for example, L2≤36.5mm, L1≤20mm), the chip heat dissipation is limited, resulting in a higher chip temperature and greater thermal stress; especially the factor of the ratio of the RC-IGBT chip length L3 to the RC-IGBT chip width L4 (that is, the aspect ratio) is too large. At this time, the stress concentration on the large aspect ratio chip increases sharply, the thermal expansion non-uniformity increases sharply at high temperature, and the stress difference between different regions increases sharply. Therefore, in the small package, the RC-IGBT is a large current specification, and the RC-IGBT has a large aspect ratio. The three factors work together to easily lead to a sharp increase in the probability of chip failure.

[0089] Therefore, in the embodiment of the present application, when 26A≤I≤35A, the aspect ratio of the RC-IGBT is less than or equal to 1.61, for example, 1.61, 1.5, 1.45, 1.4, 1.35, 1.3, or 1.2, etc. In some examples, the aspect ratio of the RC-IGBT can be further made less than 1.1.498, and in other examples, it can be less than or equal to 1.4, so as to reduce the chip stress under high current specifications and make the stress increase more moderate, thereby effectively solving the problem of uneven thermal expansion at high temperature and greatly reducing the failure probability of chips with high current specifications.

[0090] Furthermore, when the heat dissipation substrate area S is 161.25 mm 2 -275mm 2 Although the heat dissipation of the chip is further restricted, the aspect ratio of the RC-IGBT is reduced by making the aspect ratio of the RC-IGBT less than or equal to 1.61, thereby reducing the chip aspect ratio under the large current specification (26A≤I≤35A), so that the above-mentioned small package and small heat dissipation substrate (for example, L2≤36.5mm, L1≤20mm, 161.25mm 2 ≤ Heat dissipation substrate area S≤275mm 2 ) can reduce chip stress concentration under high current specifications, effectively solve the problem of uneven thermal expansion at high temperature, and greatly reduce the failure probability of chips with high current specifications, which is conducive to providing a semiconductor device (such as a power module) that has miniaturization, high current specifications and high reliability.

[0091] If the aspect ratio is too small, for example, less than or equal to 1.18, it means that the width of the RC-IGBT chip increases (that is, the lateral size increases). According to the current circuit pattern design on the heat dissipation substrate, the lateral size of the power side pad 31 used to connect to the RC-IGBT is much smaller than the longitudinal size, and the corresponding RC-IGBT lateral variable size is much smaller than the chip longitudinal variable size. Therefore, the larger width of the RC-IGBT is not conducive to the miniaturization of the semiconductor device. Therefore, in some embodiments, the aspect ratio of the RC-IGBT is greater than 1.18, that is, the longitudinal size is relatively large, which can be more conducive to the miniaturization of the semiconductor device. In some embodiments, the aspect ratio of the RC-IGBT is less than or equal to 1.59 and greater than or equal to 1.45, or other suitable ranges, which are not specifically limited here.

[0092] It is worth mentioning that in the embodiment of the present application, the aspect ratio of the RC-IGBT is the ratio of the length L3 and the width L4 of the RC-IGBT. In this article, the length L3 is usually greater than the width L4. Among them, the width direction of the encapsulation resin is generally parallel to the length direction of the RC-IGBT, so the length L3 of the RC-IGBT in the length direction is also the size of the RC-IGBT in the width direction of the encapsulation resin, and the length direction of the encapsulation resin is generally parallel to the width direction of the RC-IGBT, so the width L4 of the RC-IGBT in the width direction is also the size of the RC-IGBT in the length direction of the encapsulation resin.

[0093] If the width of the RC-IGBT is too small, the aspect ratio of the RC-IGBT may be increased. As mentioned above, a large aspect ratio is likely to increase the failure probability of the RC-IGBT, and if the width is too large, it is also likely to increase the overall size of the power module. Therefore, in some embodiments, the width L4 of the RC-IGBT is greater than or equal to 2.0 mm and less than or equal to 3.4 mm, so that the aspect ratio of the RC-IGBT will not be too large, thereby reducing the probability of chip failure and not increasing the overall size of the product.

[0094] Based on the above similar analysis, in some embodiments, when 45A≤I≤55A, the size of the corresponding small package satisfies the following constraints: L2≤40mm, L1≤26mm, and the corresponding RC-IGBT has an aspect ratio less than or equal to 1.56, such as 1.5, 1.45, 1.4, 1.35, 1.3, or 1.2, etc. The aspect ratio of the RC-IGBT is also greater than 1.1, that is, the longitudinal dimension is relatively large, which can be more conducive to miniaturization of the semiconductor device. In some embodiments, the aspect ratio of the RC-IGBT is less than or equal to 1.56 and greater than or equal to 1.45.

[0095] Based on the above similar analysis, in other embodiments, when 70A≤I≤80A, the corresponding small package has the following size constraints: L2≤60mm, L1≤33mm, and the corresponding RC-IGBT has an aspect ratio less than or equal to 1.48, such as 1.46, 1.45, 1.4, 1.35, 1.3, or 1.2, etc. The aspect ratio of the RC-IGBT can be further made less than 1.45. In other examples, it can also be less than or equal to 1.4 to reduce the chip stress under high current specifications and make the stress increase more gentle, thereby effectively solving the problem of uneven thermal expansion at high temperature and greatly reducing the probability of failure of high current specification chips. In some embodiments, the aspect ratio of the RC-IGBT is also greater than 1, that is, the longitudinal dimension is relatively large, which can be more conducive to miniaturizing the semiconductor device. In some embodiments, the aspect ratio of the RC-IGBT is less than or equal to 1.45 and greater than or equal to 1.3, or other suitable ranges, which are not specifically limited here.

[0096] Furthermore, in order to improve the heat dissipation effect of the power module, at least part of the second surface of the heat dissipation substrate 30 (also referred to as the bottom surface of the heat dissipation substrate) is exposed from the encapsulation resin. For example, the bottom surface of the heat dissipation substrate 30 is exposed from the encapsulation resin, while the other surfaces are covered by the encapsulation resin. Through such an arrangement, the heat dissipation performance of the heat dissipation substrate to the outside of the power module can be improved, thereby improving the stability and reliability of the power module. In one example, the second surface of the heat dissipation substrate can also be flush with the bottom surface of the encapsulation resin.

[0097] Figure 4 shows a top view of the power module, which is Figure 2 and Figure 3A , which does not show some details inside the encapsulation resin. In some embodiments, such as Figure 5 , Figure 7 and Fig. 9 As shown, the heat dissipation substrate 30 has a first surface 3001 and a second surface 3002 arranged opposite to each other, wherein the RC-IGBT is arranged on the first surface 3001 of the heat dissipation substrate 30. In some examples, such as 5, Figure 7 and Fig. 9 As shown, the heat dissipation substrate 30 includes an insulating layer 303 and a conductive layer, the insulating layer 303 has a first surface 3031 and a second surface 3032 opposite to the first surface 3031, and the conductive layer is at least arranged on the first surface 3031 of the insulating layer 303. The insulating layer 303 may be a ceramic layer, and the ceramic layer may have a relative Al 2 O 3 A ceramic material having a higher thermal conductivity, such as at least one of an aluminum nitride ceramic layer or a silicon nitride ceramic layer, is used to 2 O 3Ceramic materials with higher thermal conductivity can improve the heat dissipation of the heat dissipation substrate, thereby dissipating the heat generated by, for example, the RC-IGBT and the conductive layer, which is beneficial to reducing the temperature of the power module 100, thereby suppressing the heat accumulation generated during the operation of the power module 100 and ensuring safety. In addition, the insulating layer can also play an insulating role, which can isolate the conductive layer electrically connected to the RC-IGBT from being electrically connected to the outside world, thereby ensuring the normal operation of the power module 100 and improving the electrical safety of the power module 100.

[0098] In other embodiments, the conductive layer of the heat dissipation substrate 30 may be at least two layers, for example, the conductive layer includes a first conductive layer 301 and a second conductive layer 302, the first conductive layer 301 is arranged on the first surface 3031 of the insulating layer 303, and the second conductive layer is arranged on the second surface 3032 of the insulating layer 303, the surface of the first conductive layer 301 away from the insulating layer 303 constitutes at least a portion of the first surface 3001 of the heat dissipation substrate 30, and the surface of the second conductive layer 302 away from the insulating layer 303 constitutes at least a portion of the second surface 3002 of the heat dissipation substrate 30, then at least a portion of the surface of the second conductive layer 302 is exposed in the encapsulation resin 10.

[0099] Optionally, the material of the conductive layer may be a metal material, such as one or more of copper, aluminum, silver, gold, tin and the like. For example, the material of the conductive layer includes copper.

[0100] In some embodiments, for example, a pattern may be etched on the first conductive layer 301 of the copper layer, and the pattern may correspond to a power side pad 31 corresponding to one or more RC-IGBTs, and the first conductive layer includes a power side pad 31, and there is a gap between adjacent power side pads 31, and the gap exposes part of the insulating layer 303, and the copper layer can carry the RC-IGBT and play a conductive role. For the heat dissipation substrate 30 with the second conductive layer 302, the second conductive layer 302 may be non-patterned, and it is exposed from the bottom surface of the plastic package, and the second conductive layer 302 has the characteristic of good thermal conductivity, and the heat dissipation of the heat dissipation substrate 30 is further improved, so that the normal operation of the power module 100 can be ensured, which is conducive to improving the electrical safety of the power module 100.

[0101] The heat dissipation substrate 30 can be made by any suitable process, for example, active metal brazing technology (AMB), which uses active metal solder containing a small amount of active metal elements (Ti, Zr, Hf, V, Nb or Ta) to achieve welding between metal such as copper foil and ceramic substrate (i.e., insulating layer). The above-mentioned metal elements are highly active and can improve the wettability of the solder to the ceramic after melting, so that the ceramic surface can be welded with the metal without metallization. The general process of the process is as follows: first, the brazing material is coated on the ceramic substrate, and then brazing and sintering are performed at high temperature in vacuum, the copper layer is welded to the ceramic substrate, and then the circuit pattern is photolithography and copper etching are performed, and finally the active metal solder layer is etched. The copper / ceramic interface formed by the AMB process has better bonding strength. When the insulating layer in the embodiment of the present application is an aluminum nitride ceramic layer or a silicon nitride ceramic layer, the heat dissipation substrate 30 made by active metal brazing technology can be used. In some other embodiments, the first conductive layer can also be at least a part of a metal frame, for example, and can be arranged on the insulating layer by welding or bonding.

[0102] like Figures 2 to 8C As shown, the heat dissipation substrate 30 has a first side 311 and a second side 312 opposite to each other in the length direction, and a third side 313 close to the driving integrated circuit. The second conductive layer 302 includes a main body 3022 and an extension 3021 connected to the main body. The extension 3021 is extended to the outside of the insulating layer 303 and the outside of the first conductive layer 301, that is, the extension 3021 is extended to the outside of the side wall of the insulating layer 303 and the side wall of the first conductive layer 301 (it can also be called a protruding setting), and the main body 3022 can be the inner side of the side wall of the insulating layer, for example, the main body 3022 covers the second surface 3032 of the insulating layer. The extension 3021 can be set on at least one of the first side 311, the second side 312 and the third side 313, and can be reasonably selected according to the current specification of the actual chip and the size of the packaging resin.

[0103] Further, if Figure 2 , Figures 4 to 6As shown, at least one core-pulling pin hole 110 is provided on the side of the encapsulation resin 10 opposite to the second surface of the heat dissipation substrate 30. The projection of the core-pulling pin hole 110 in the thickness direction of the encapsulation resin 10 partially overlaps with the corresponding extension 3021, and is located outside the insulating layer 303 and the first conductive layer 301. Since the spatial position of the core-pulling pin hole corresponds to the position of the core-pulling pin during encapsulation, the core-pulling pin corresponding to the core-pulling pin hole 110 partially falls on the extension and is located outside the insulating layer during encapsulation, so that during encapsulation, the core-pulling pin presses the extension 3021 without exerting force on the insulating layer, thereby avoiding pressing the insulating layer, while avoiding the overflow of the glue on the second surface of the heat dissipation substrate, preventing the rupture of the insulating layer, thereby ensuring the reliability and yield of the module. In addition, since the core-pulling pin presses the extension of the second conductive layer, it is not easy to interfere with the power chip on the first conductive layer, which is conducive to setting a power chip with a larger size on the heat dissipation substrate to improve the product's flow capacity and power, and it can also be conducive to setting the power chip close to the edge of the first conductive layer, thereby reducing the inductance.

[0104] In some embodiments, the center of the projection of each core-pulling needle hole 110 in the thickness direction of the encapsulation resin 10 is located on the extension portion 3021. Through such a setting, the center of the core-pulling needle is also located on the extension portion 3021 during encapsulation, thereby ensuring that the core-pulling needle can fully contact the extension portion 3021 and apply pressure to it, thereby better ensuring that the second side of the heat dissipation substrate and the plastic encapsulation mold fit together, and avoiding glue overflow on the second side of the heat dissipation substrate.

[0105] In some embodiments, Figure 2 , Figure 4 and Figure 5 As shown, the number of the core-pulling pinholes 110 can be one or more, and can be reasonably set according to actual needs. For example, the number of the core-pulling pinholes 110 can be two, and the projections of the two core-pulling pinholes 110 in the thickness direction correspond to the extensions 3021 of the first side 311 and the second side 312 of the heat dissipation substrate 30, for example, the corresponding corners of the extensions close to the driver integrated circuit. In other embodiments, when the extension 3021 is provided on the third side 313 of the heat dissipation substrate 30, the projection of the core-pulling pinhole 110 falls on the extension 3021 of the third side 313. In still other embodiments, when the first side 311, the second side 312 and the third side 313 of the heat dissipation substrate 30 all have extensions 3021, the extensions 3021 on each side correspond to one or more core-pulling pinholes 110.

[0106] like Figure 6 As shown, the core-pulling needle hole 110 is a generally cylindrical depression, and a sleeve hole is also provided on the outer side thereof. The diameter of the sleeve hole is larger than that of the core-pulling needle hole 110 , but the depth of the core-pulling needle hole 110 is larger than that of the sleeve hole.

[0107] As shown in Figure 3 and Figure 7 As shown, in some embodiments, the projection area of ​​each core-pulling pinhole in the thickness direction of the encapsulation resin is set as S, and the overlapping area of ​​the projection of each core-pulling pinhole in the thickness direction of the encapsulation resin and its corresponding extension portion is set as S1, then With this arrangement, during packaging, the center of gravity of the core-pulling needle falls on the extension part, which can better achieve the pressing effect and avoid glue overflow on the second side of the heat dissipation substrate. When the core pulling needle is pressed, the center of gravity of the core pulling needle falls on the outside of the extension part, and the core pulling needle is prone to tilt, which cannot effectively avoid glue overflow on the second side of the heat dissipation substrate, affecting the packaging effect.

[0108] In some embodiments, as shown in FIG. 3 and Figure 7 As shown, the spacing distance between the projection of the core-pulling needle hole 110 on the extension portion 3021 and the adjacent insulating layer 303 is set to A, then A≥0.3mm. That is, the spacing distance between the projection of the core-pulling needle hole 110 and the side edge of the adjacent insulating layer 303 is A. Its projection corresponds to the landing point of the core-pulling needle 111. In order to facilitate the understanding of this distance, the core-pulling needle 111 is used to illustrate the core-pulling needle hole 110 in the figure. By making it ≥0.3mm, it can be ensured that the core-pulling needle 111 directly presses the extension portion 3021 of the second conductive layer 302 during packaging, and the spacing distance A can also ensure a safe distance between the core-pulling needle 111 and the insulating layer 303, avoiding pressing the insulating layer 303, and preventing the insulating layer 303 from rupturing while avoiding glue overflow on the second side of the ceramic heat dissipation substrate.

[0109] In some embodiments, as shown in FIG. 3 and Figure 7 As shown, the distance between the edge of the extension 3021 and the edge of the insulating layer 303 adjacent thereto is set to B, and the radius of the projection of each core-pulling needle hole 110 in the thickness direction of the encapsulation resin 10 is set to R, then B satisfies the following formula: B≥R+0.3, that is, B≥R+0.3mm, for example, B≥0.9mm. With such a setting, during encapsulation, the center of gravity of the core-pulling needle 111 falls on the extension 3021, which can better achieve the pressing effect and avoid the glue overflowing from the second side of the heat dissipation substrate 30. If B<R+0.3, the center of gravity of the core-pulling needle is outside the extension 3021, and the core-pulling needle is prone to tilt during pressing, which cannot well avoid the glue overflowing from the second side of the heat dissipation substrate, thereby easily affecting the encapsulation effect.

[0110] In some embodiments, FIG. 8A to FIG. 8C As shown, for different sizes of encapsulation resin, the corresponding extension portion may be arranged differently, for example, Fig. 8AAs shown, when the volume of the encapsulation resin 10 is within the first threshold range (also referred to herein as a small package body), an extension portion 3021 is provided on both the first side 311 and the second side 312, that is, the second conductive layer 302 is integrally extended outward on both sides in the length direction, that is, the length of the second conductive layer 302 is increased, and its length is greater than the length of the insulating layer 303, and greater than the length of the first conductive layer 301. In some examples, the length of the insulating layer 303 is greater than the length of the first conductive layer 301, and the width of the insulating layer 303 is greater than the width of the first conductive layer 301 and the width of the second conductive layer 302. More specifically, the first conductive layer 301 covers the portion The insulating layer 303 is divided so that the edges of the first conductive layer 301 are located on the inner sides of the edges of the insulating layer 303, and the edges of the second conductive layer 302 in the width direction are located on the inner sides of the edges of the insulating layer 303 in the width direction. The core pulling needles are arranged on the extension part 3021 of the first side 311 and the second side 312 as needed. This type of heat dissipation substrate is suitable for small packages. Specifically, when the volume of the packaging resin 10 is within the first threshold range, 16mm≤L1≤20mm, and 31.5mm≤L2≤36.5mm, that is, the size of the packaging resin 10 when the current specification of the corresponding power chip is 26A≤I≤35A.

[0111] For example, Figure 8B As shown, when the volume of the packaging resin 10 is within the second threshold range (also referred to as a middle package body in this article), an extension portion 3021 is provided on the third side 313, that is, the third side of the second conductive layer 302 is extended outward as a whole, that is, the width of the second conductive layer 302 is increased, and a core pulling needle is provided on the extension portion 3021 of the third side 313 as needed. This type of heat dissipation substrate is suitable for a middle package body. Specifically, when the volume of the packaging resin 10 is within the second threshold range, its size satisfies the following constraints: 36mm≤L2≤40mm, and 22mm≤L1≤26mm, that is, the size of the packaging resin 10 when the current specification of the corresponding power chip is 45A≤I≤55A.

[0112] For example, Figure 8CAs shown, when the volume of the encapsulation resin 10 is within the third threshold range (also referred to as a large package body in this article), extensions are provided on the first side 311, the second side 312 and the third side 313, that is, the first side 311, the second side 312 and the third side 313 of the second conductive layer 302 are extended outward as a whole, that is, the length and width of the second conductive layer 302 are increased, and the core-pulling needle is provided on the extension 3021 of the first side 311, the second side 312 and the third side 313 as required. This type of heat dissipation substrate is suitable for a large package body. Specifically, when the volume of the encapsulation resin 10 is within the third threshold range, its size satisfies the following constraints: 29mm≤L1≤33mm, and 50mm≤L2≤60mm, that is, the size of the encapsulation resin 10 corresponding to the current specification of the power chip is 70A≤I≤80A. Among them, the upper limit value of the first threshold range is less than the lower limit value of the second threshold range, and the upper limit value of the second threshold range is less than the lower limit value of the third threshold range.

[0113] By matching the appropriate heat dissipation substrate type to the packages of different sizes, the pressing effect of the core pulling needle can be better achieved, and glue overflow on the second surface of the heat dissipation substrate 30 can be avoided.

[0114] In some examples, the length of the insulating layer 303 is greater than the length of the first conductive layer 301, and the width of the insulating layer 303 is greater than the width of the first conductive layer 301 and the width of the second conductive layer 302. More specifically, the first conductive layer 301 covers part of the insulating layer 303, so that the edges of the first conductive layer 301 are located inside the edges of the insulating layer 303, and the edge of the side of the second conductive layer where the extension is not provided is located inside the edge of the corresponding insulating layer 303. Through such a configuration, a longer creepage distance can be provided between the first conductive layer and the second conductive layer, thereby improving electrical safety. Figure 1A and 1BAs shown, in some related technologies, a row of 6 power chips are arranged on the circuit wiring copper layer of the heat dissipation substrate. During packaging, the core pulling needle presses the conductive layer (i.e., the copper layer) on the ceramic layer. In order to meet the pressing requirement of the core pulling needle on the heat dissipation substrate and avoid the core pulling needle pressing the power chip, the spacing distance between the edge of the power chip close to the core pulling needle and the edge of the conductive layer on the side close to the driver integrated circuit is larger, for example, the minimum is 0.8mm, that is, greater than 0.8mm, which will lead to a waste of area of ​​the conductive layer on the ceramic layer, affecting the effective area actually used to place the power chips on the heat dissipation substrate, and making the 6 power chips The power chips are staggered in the width direction, especially the two power chips on both sides of the length direction. This arrangement requires longer connecting wires to connect the two power chips to the corresponding driver integrated circuit, which increases the cost of the product. The longer connecting wires are prone to deformation, and the increased gate inductance affects the switching characteristics of the power chip. In addition, without changing the overall size of the DBC, a larger power chip needs to be set to increase the product's current capacity and power. There is a risk that the large-size power chip may interfere with the core pulling pin, making it impossible for the module to take into account the needs of reducing gate inductance, improving product current capacity, and avoiding interference with the core pulling pin.

[0115] Since the heat dissipation substrate in the embodiment of the present application has an extension portion, the core pulling needle can press the extension portion of the second conductive layer accordingly, which significantly reduces the risk of interference between the core pulling needle and the power chip, and is conducive to integrating large-size power chips and improving the product's current capacity. In some embodiments, the number of power chips is multiple, for example 6, and the multiple power chips are arranged on the heat dissipation substrate 30 at intervals along the length direction, wherein the edges of the multiple power chips close to the driver integrated circuit (for example, close to the driver side frame) are flush. By making the edge of the power chip close to the driver integrated circuit flush, the spacing distance between the power chip and the driver integrated circuit can be reduced as much as possible, which is conducive to reducing the length of the connecting line between the two, thereby reducing the gate inductance and reducing the switching loss. Such a setting is also conducive to integrating larger-sized power chips to improve the product's current capacity and power.

[0116] like Figure 4 As shown, in some embodiments, the distance between the edge of the multiple power chips close to the driver integrated circuit and the edge of the first conductive layer close to the driver integrated circuit is less than 0.8mm. For example, if the distance is set to C, C < 0.8mm. Furthermore, C can be in the range of 0.35mm-0.65mm. Specifically, it can be reasonably set according to actual needs. Through such a setting, the spacing distance between the power chip and the driver integrated circuit can be reduced as much as possible, which is conducive to reducing the length of the connecting line between the two, thereby reducing the gate inductance and reducing the switching loss. Such a setting is also conducive to integrating a larger size power chip to improve the product's current capacity and power.

[0117] In some embodiments, Fig. 9 As shown, an inner groove 3033 recessed inwardly from the side of the insulating layer 303 is provided in the insulating layer 303, for example, one side opening of the inner groove 303 faces the second conductive layer 302, that is, the insulating layer 303 includes a first portion close to the second conductive layer 302 and a second portion away from the second conductive layer 302, wherein the first portion is shorter in length and width than the second portion, thereby forming an inner groove 3033 recessed inwardly on the side of the insulating layer 303, or, the opening of the inner groove 3033 may not face the second conductive layer 302 but has an opening facing the outside of the insulating layer, and by providing the inner groove 3033, the creepage distance of the second conductive layer 302 can be increased, thereby improving electrical safety.

[0118] In some embodiments, the distance from the opening of the inner groove 3033 located on the side of the insulating layer to the bottom surface of the inner groove 3033 opposite to the opening can be the same as or greater than the distance between the edge of the first conductive layer 301 and the edge of the adjacent insulating layer 303. By reasonably setting this distance of the inner groove 3033, the creepage distance of the second conductive layer 302 can be effectively increased, thereby improving electrical safety.

[0119] The following will be combined Figure 2 and Figure 3A Some exemplary layouts of intelligent power chips are described, but this does not constitute a limitation of the present application, and the layout can also be reasonably adjusted according to actual needs. In some embodiments, multiple power chips such as RC-IGBT include at least one high-voltage power side RC-IGBT321 and at least one low-voltage power side RC-IGBT331, and the high-voltage power side RC-IGBT321 and the low-voltage power side RC-IGBT331 are respectively arranged on different power side pads 31. By arranging at least one high-voltage power side RC-IGBT321 and at least one low-voltage power side RC-IGBT331 on different power side pads 31, different types of RC-IGBTs can be better electrically isolated, so that the connection of the required connection structure can be achieved through pins and connecting wires, which is conducive to the normal operation of the power module.

[0120] Optionally, multiple RC-IGBTs can be laid out according to actual needs. In the embodiment of the present application, some details of the power module are described mainly by taking the case where the number of low-voltage power side RC-IGBTs is three and the number of high-voltage power side RC-IGBTs is three as an example, but this is not intended to constitute a limitation. In some possible embodiments, there may also be other different numbers of high-voltage power side RC-IGBTs or low-voltage power side RC-IGBTs.

[0121] In some embodiments, the power side pad 31 of the heat dissipation substrate 30 includes a low-voltage power side pad 33 and a high-voltage power side pad 32, wherein there are three low-voltage power side pads 33, which are spaced apart in the length direction of the encapsulation resin, and there is one high-voltage power side pad 32, which is spaced apart from the three low-voltage power side pads 33 in the length direction of the encapsulation resin, and the two sides of the encapsulation resin along its length direction are respectively the first side 11 and the second side 12, and the low-voltage power side pad 33 is closer to the first side 11 in the length direction, and the high-voltage power side pad 32 is closer to the second side 12 in the length direction of the encapsulation resin. Through such a setting, the layout of the power module can be made more reasonable, and the arrangement of the leads connected to the pads can be made more concise and regular.

[0122] Optionally, three low-voltage power-side RC-IGBTs 331 are respectively arranged on three low-voltage power-side pads 33 in one-to-one correspondence, and three high-voltage power-side RC-IGBTs 321 are all arranged on one high-voltage power-side pad 32, and the three high-voltage power-side RC-IGBTs are arranged at intervals along the length direction of the packaging resin on the high-voltage power-side pad 32. By making three high-voltage power-side RC-IGBTs correspond to one high-voltage power-side pad 32, the number of pins and wires can be reduced, the layout structure of the power module can be simplified, and the structure is more compact, which is conducive to the miniaturization of the power module.

[0123] In some other embodiments, each high-voltage power side RC-IGBT 321 may correspond to one high-voltage power side pad 32, or two high-voltage power side RC-IGBTs may correspond to one high-voltage power side pad. Alternatively, in some other embodiments, at least two low-voltage power side RC-IGBTs may correspond to one low-voltage power side pad. Specifically, it may be reasonably set according to actual needs.

[0124] In some embodiments, in order to meet reasonable lead layout requirements, the first conductive layer 301 of the heat dissipation substrate 30 may further have a jumper area (not shown).

[0125] More specifically, in some embodiments, the power module 100 also includes power side pins 34, part of which is wrapped by the packaging resin and is located on the side of the heat dissipation substrate 30 away from the driving integrated circuit 20 along the width direction of the packaging resin. The power side pins 34 are electrically connected to the RC-IGBT, and the electrical connection of the external circuit of the RC-IGBT can be achieved through the power side pins.

[0126] In some embodiments, each RC-IGBT includes: a gate pad 35 and an emitter pad 36, the gate pad 35 is electrically connected to the driver integrated circuit, a pin electrical connection solder joint 361 is arranged on the emitter pad 36, a pin electrical connection wire 262 is connected between the pin electrical connection solder joint 361 and the power side pin 34, the pin electrical connection solder joint 361 is extended in the width direction of the packaging resin, a plurality of pin electrical connection solder joints 361 are arranged on each RC-IGBT, a plurality of pin electrical connection solder joints 361 on each RC-IGBT are arranged at intervals in the width direction of the packaging resin, a plurality of pin electrical connection wires 262 are arranged between each RC-IGBT and the corresponding power side pin 34, and a plurality of pin electrical connection wires 262 of each RC-IGBT are connected one-to-one with a plurality of pin electrical connection solder joints 361. By such a setting, the electrical connection between the RC-IGBT and the corresponding pin can be realized, and the normal function of the power module can be realized by making the RC-IGBT form a suitable circuit structure.

[0127] One end of each power-side pin 34 for electrical connection to the RC-IGBT is wrapped by the packaging resin, while the other end of the power-side pin 34 extends out of the packaging resin to facilitate electrical connection to an external circuit.

[0128] In some embodiments, the two sides of the encapsulation resin along its length direction are set to be the first side 11 and the second side 12 respectively, and the pin electrical connection line 262 extends obliquely relative to the pin electrical connection solder joint 361 toward the side of the width direction of the encapsulation resin close to the first side 11, and an angle α is formed between the pin electrical connection line 262 and the pin electrical connection solder joint 361, and α satisfies the relationship: 120°≤α≤178°. By making the angle α satisfy the above relationship, it can be more convenient to wire the pin electrical connection line, and it can also ensure the insulation distance between multiple pin electrical connection lines, so as to avoid short circuits of the pin electrical connection lines due to too close distance, thereby damaging the device.

[0129] In some embodiments, the length of the pin electrical connection line 262 is set to L5, then L5 satisfies the relationship: 5mm≤L5≤9mm. Through such a setting, it can be ensured that the length of the pin electrical connection line 262 satisfies the normal electrical connection between the emitter of the RC-IGBT and the power side pin 34, while also suppressing the problems of material waste, increased resistance and increased inductance caused by the excessive length of the pin electrical connection line, thereby reducing the power consumption of the power module and improving the stability of the power module.

[0130] It is worth mentioning that in the embodiment of the present application, the number of pin electrical connection lines 262 for connecting each RC-IGBT and the corresponding power-side pin can be 1, or greater than or equal to 2. The drawings of the present application mainly show the case where the number of pin electrical connection lines 262 is greater than 2, but this is not intended to constitute a limitation.

[0131] Further, in some embodiments of the present application, a driving side frame 20 is also included, part of which is wrapped by a packaging resin, and the driving side frame 20 includes a driving side pad 21 and a driving side pin 24, and a driving integrated circuit is arranged on the driving side pad 21, and the driving integrated circuit is electrically connected to the driving side pin 24, wherein the heat dissipation substrate 30 and the driving side frame 20 are arranged at intervals in the width direction. Optionally, part of the driving side pin 24 extends out from the packaging resin to facilitate its electrical connection with an external circuit. Using the driving side frame to set the driving integrated circuit and integrate the driving side pin can be conducive to achieving high integration, and can also reduce the number of components, reduce the overall size, and make the power module structure more compact. It can also enhance heat dissipation and improve the stability and reliability of the power module.

[0132] In other embodiments, a PCB board can also be used to replace the drive side frame 20, the PCB board (also known as a printed circuit board) is wrapped by a packaging resin, the PCB board has a drive side pad, the power module also includes a drive side pin (for example, the drive side pin and the PCB board are two independent devices), the drive side pin is electrically connected to the PCB board (for example, the drive side pin and the PCB board are electrically connected by welding or other suitable methods), the drive side pin is electrically connected to the PCB board, a driver integrated circuit is arranged on the drive side pad, and the driver integrated circuit is electrically connected to the drive side pin, wherein the heat dissipation substrate 30 and the PCB board are arranged at intervals in the width direction of the packaging resin. The side of the PCB board used to set the driver integrated circuit can have various wirings and pad areas for placing the driver integrated circuit, and the wiring can realize the electrical connection between each pad area and the corresponding drive side pin or structure. Specifically, the structure of the PCB board can be reasonably selected according to actual needs, and is not specifically limited here. The wiring and support of the driver integrated circuit can be realized by the PCB board, and the PCB board has a simple structure and is more friendly to packaging. In some examples, the driving side pins and the corresponding driving side pads on the PCB board can be electrically connected by, for example, welding, connector connection, bonding wires, or spring connection, which are not specifically limited here.

[0133] A PCB board can be a substrate that forms electrical connections between electronic components by, for example, patterning conductive copper foil on the surface of an insulating material (such as glass fiber, epoxy resin, etc.). The PCB board realizes electrical connections between electronic components through these copper foil lines and supports components to be fixed on the board. Optionally, the PCB board can be a single-sided board, a double-sided board, or a multi-sided board.

[0134] The following will take the driving side frame 20 as an example to explain some details of the driving side frame 20 .

[0135] In some embodiments, the driving side pad 21 includes a low-voltage driving side pad 23 and a high-voltage driving side pad 22, the low-voltage driving side pad 23 is one, the high-voltage driving side pad 22 is one, one high-voltage driving side pad 22 and one low-voltage driving side pad 23 are spaced apart in the length direction, and the two sides of the packaging resin along the length direction are set to be the first side 11 and the second side 12 respectively, the low-voltage driving side pad 23 is closer to the first side 11 in the length direction, and the high-voltage driving side pad 22 is closer to the second side 12 in the length direction, and the driving integrated circuit includes a low-voltage driving integrated circuit 231 and a high-voltage driving integrated circuit 221, one low-voltage driving integrated circuit 231 is arranged on one low-voltage driving side pad 23, and one A high-voltage driver integrated circuit 221 is arranged on a high-voltage driver side pad 22, wherein, when the number of RC-IGBTs is multiple, and the multiple RC-IGBTs include multiple low-voltage power side RC-IGBTs and multiple high-voltage power side RC-IGBTs, a low-voltage driver integrated circuit 231 is electrically connected to multiple low-voltage power side RC-IGBT331 (for example, a low-voltage driver integrated circuit 231 is electrically connected to three low-voltage power side RC-IGBT331), and a high-voltage driver integrated circuit 221 is electrically connected to multiple high-voltage power side RC-IGBT321, for example, a high-voltage driver integrated circuit 221 is electrically connected to three high-voltage power side RC-IGBT331. In this way, the layout of the power module can be made more reasonable, and the lead distribution between the driver integrated circuit and the RC-IGBT can be made more balanced.

[0136] Further, in some embodiments, the power module further includes a bootstrap chip 251, which is disposed on the drive side pin 24, wherein the drive side pin 24 further includes: a floating supply voltage pin 241, which is disposed at intervals on a side of the high voltage drive side pad 22 away from the heat dissipation substrate 30 in the width direction, and the floating supply voltage pin 241 has a bootstrap chip pad 25, and the bootstrap chip 251 is disposed on the bootstrap chip pad 25. Optionally, three high voltage power sides may correspond to three bootstrap chips (for example, a circuit including a bootstrap diode), and the bootstrap chip may be used to isolate the power supply, increase the drive voltage, and realize automatic gain control, and by arranging the bootstrap chip on the drive side pin, the circuit layout and wiring may be optimized, which is beneficial to the miniaturization of the power module.

[0137] In some embodiments, the driving side pin 24 also includes a suspended power supply ground pin 242, which is spaced apart on the side of the high-voltage driving side pad 22 away from the heat dissipation substrate 30 in the width direction, and the suspended power supply ground pin 242 is spaced apart from the suspended power supply voltage pin 241 in the length direction.

[0138] It is worth mentioning that, in some embodiments, the floating power supply pin 242 may not be provided.

[0139] In some embodiments, the driving side pin 24 also includes a chip power supply voltage pin 243, which is extended in the length direction and spaced between the high-voltage driving side pad 22 and the floating power supply voltage pin 241 in the width direction. The bootstrap chip 251 is electrically connected to the chip power supply voltage pin 243, and the floating power supply voltage pin 241 and the floating power supply ground pin 242 are both electrically connected to the high-voltage driving integrated circuit 221.

[0140] In some other embodiments, the bootstrap chip can also be integrated into a high-voltage driver integrated circuit, wherein the driver side pin 24 is implemented to include the following structure and electrical connection relationship, for example, the driver side pin 24 includes a floating power supply voltage pin 241, a floating power supply ground pin 242 and a chip power supply voltage pin 243, the floating power supply voltage pin 241 is spaced apart on the side of the high-voltage driver side pad 22 away from the heat dissipation substrate 30 in the width direction; the floating power supply ground pin 242 is spaced apart on the side of the high-voltage driver side pad 22 away from the heat dissipation substrate 30 in the width direction, and the floating power supply ground pin 242 and the floating power supply voltage pin 241 are spaced apart in the length direction; the chip power supply voltage pin 243 is extended in the length direction and spaced apart in the width direction between the high-voltage driver side pad 22 and the floating power supply voltage pin 241, the high-voltage driver integrated circuit 221 is electrically connected to the chip power supply voltage pin 243, and the floating power supply voltage pin 241 and the floating power supply ground pin 242 are both electrically connected to the high-voltage driver integrated circuit 221. By integrating the bootstrap chip into the high-voltage driver integrated circuit, the circuit design can be simplified, the number of components and connections can be reduced, space can be saved, the complexity and failure rate of the power module can be reduced, and the miniaturization of the power module can be facilitated. It is worth mentioning that in other embodiments, in order to reduce the space occupied by the drive side pins, the chip power supply voltage pin 243 may not cross other pins in the length direction.

[0141] The introduction to the power module in the embodiment of the present application has been completed so far, but it is conceivable that in addition to the above structure, there may be other suitable components, which are not specifically limited here.

[0142] To sum up, since the spatial position of the core pulling pin hole corresponds to the position of the core pulling needle during packaging, during packaging, the core pulling pin corresponding to the core pulling pin hole partially falls on the extension part and is located on the outside of the insulating layer, so that during packaging, the core pulling pin presses the extension part without exerting force on the insulating layer, thereby avoiding pressing the insulating layer. While avoiding glue overflow on the second side of the ceramic substrate, the rupture of the insulating layer is prevented, thereby ensuring the reliability and yield of the module. Moreover, since the core pulling pin presses the extension part of the second conductive layer, it is not easy to interfere with the power chip on the first conductive layer, which is conducive to arranging a power chip with a larger size on the heat dissipation substrate to improve the product's current capacity and power, and can also help to arrange the power chip close to the edge of the first conductive layer, thereby reducing inductance.

[0143] In another aspect of the present application, an electronic device is provided, the electronic device includes the aforementioned power module, wherein the electronic device may include household appliances, such as electric fans, air conditioners, kitchen hoods, high-speed air ducts, washing machines, etc., and the power module may be used in the motor drive system of household appliances. The electronic device may also be a new energy vehicle, industrial automation equipment, switching power supply, etc.

[0144] Since the electronic device of the present application has the aforementioned power module, it also has the advantages of the aforementioned power module.

[0145] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application to this. Those of ordinary skill in the art may make various changes and modifications therein without departing from the scope and spirit of the present application. All these changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0146] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0147] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various inventive aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the corresponding claims, the inventive point is that the corresponding technical problem can be solved with features less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0148] It will be understood by those skilled in the art that, except for mutually exclusive features, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this specification may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0149] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims, any one of the claimed embodiments may be used in any combination.

[0150] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims.

Claims

1. A power module, comprising: Power chip; A driver integrated circuit, the driver integrated circuit is electrically connected to the power chip; A heat dissipation substrate, the heat dissipation substrate having a first surface and a second surface arranged opposite to each other, a first side and a second side opposite to each other in the length direction thereof, and a third side close to the driver integrated circuit, wherein the power chip is arranged on the first surface of the heat dissipation substrate, wherein the heat dissipation substrate comprises: an insulating layer, the insulating layer having a first surface and a second surface opposite to the first surface, wherein the insulating layer is at least one of an aluminum nitride ceramic layer or a silicon nitride ceramic layer; a first conductive layer disposed on a first surface of the insulating layer, wherein a surface of the first conductive layer away from the insulating layer constitutes at least a portion of the first surface of the heat dissipation substrate; a second conductive layer, which is disposed on a second surface of the insulating layer, the second conductive layer comprising a main body and an extension portion connected to the main body, the extension portion extending outwards of the insulating layer and the first conductive layer, wherein the extension portion is disposed on at least one of the first side, the second side and the third side; a packaging resin for packaging the power chip, the heat dissipation substrate and the driver integrated circuit, wherein at least a portion of the second surface of the heat dissipation substrate is exposed from the packaging resin, Among them, at least one core pulling pinhole is provided on the side of the packaging resin opposite to the second surface of the heat dissipation substrate, and the projection of the core pulling pinhole in the thickness direction of the packaging resin overlaps with the corresponding extension part and is located on the outside of the insulating layer and the first conductive layer.

2. The power module according to claim 1, characterized in that: The center of the projection of each of the core-pulling pin holes in the thickness direction of the encapsulation resin is located on the extension portion.

3. The power module according to claim 1, characterized in that: The projection area of ​​each of the core-pulling pinholes in the thickness direction of the encapsulation resin is set as S, and the overlapping area of ​​the projection of each of the core-pulling pinholes in the thickness direction of the encapsulation resin and the corresponding extension portion is set as S1, then 4. The power module according to claim 1, characterized in that: Assuming that the spacing distance between the projection of the core-pulling needle hole on the extension portion and the insulating layer adjacent thereto is A, then A≥0.3 mm.

5. The power module according to claim 1, characterized in that: The distance between the edge of the extension portion and the edge of the adjacent insulating layer is set to B, and the radius of the projection of each of the core-pulling pinholes in the thickness direction of the packaging resin is set to R, then B satisfies the following formula: B≥R+0.

3.

6. The power module according to claim 1, characterized in that: There are multiple power chips, and the multiple power chips are arranged on the heat dissipation substrate at intervals along the length direction, wherein the edges of the multiple power chips close to the driving integrated circuit are flush.

7. The power module according to claim 6, characterized in that: The distance between the edge of the plurality of power chips close to the driver integrated circuit and the edge of the first conductive layer close to the driver integrated circuit is less than 0.8 mm.

8. The power module according to claim 1, characterized in that: When the volume of the encapsulation resin is within a first threshold range, the extension portion is disposed on both the first side and the second side; When the volume of the encapsulation resin is within a second threshold range, providing the extension portion on the third side; When the volume of the encapsulation resin is within a third threshold range, the extension portion is provided on the first side, the second side, and the third side. The upper limit value of the first threshold range is smaller than the lower limit value of the second threshold range, and the upper limit value of the second threshold range is smaller than the lower limit value of the third threshold range.

9. The power module according to claim 8, characterized in that: The width of the encapsulation resin in the width direction is set to L1, and the length of the encapsulation resin in the length direction is set to L2, wherein: When the volume of the encapsulation resin is within the first threshold range, 16 mm ≤ L1 ≤ 20 mm, and 31.5 mm ≤ L2 ≤ 36.5 mm; When the volume of the encapsulation resin is within the second threshold range, 36 mm ≤ L2 ≤ 40 mm, and 22 mm ≤ L1 ≤ 26 mm; When the volume of the encapsulation resin is within the third threshold range, 29 mm≤L1≤33 mm, and 50 mm≤L2≤60 mm.

10. The power module according to claim 1, characterized in that: An inner groove recessed inward from a side surface of the insulating layer is arranged in the insulating layer, and one side opening of the inner groove faces the second conductive layer.

11. An electronic device, characterized in that: A power module comprising any one of claims 1-10.

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