Package and electrical system

Abstract

The utility model relates to a package and an electrical system. There is provided a package including: a mounting substrate to which at least one power chip is attached, the power chip including a power device; and a lead frame including a first chip attachment portion to which at least one collaboration device chip is attached, the collaboration device chip including a collaboration device cooperating with the power device, where heat generated by the collaboration device is lower than that generated by the power device during normal operation, and at least one first lead connected to the first chip attachment portion. Wherein the at least one first lead is coupled to the first surface of the mounting substrate so as to be electrically connected with the power chip.

Description

Technical Field

[0001] The present disclosure relates to enclosures and electrical systems including the enclosures. Background Art

[0002] Intelligent Power Module (IPM) packaging is gaining more and more attention. For IPM packaging with mature design, fine design to obtain better performance has become a trend in packaging design. On the other hand, since IPM packaging uses expensive advanced mounting substrates for mounting power-side devices, such as Direct Bond Copper (DBC) substrates to improve heat dissipation performance, this has led to a huge increase in costs.

[0003] In addition, in the prior art IPM package, the lead size of the lead frame used to connect to the DBC is mainly designed to ensure the welding strength for the welding process (e.g., solder paste welding), so the lead area is relatively large. At the same time, due to the layout of the DBC, the sizes of the leads are not exactly the same or similar, resulting in uneven distribution of the connecting leads. During molding, there is a risk of overflow of the molding compound on the back of the DBC substrate.

[0004] Therefore, there is a need in the art for improved packages and methods of making the same (packaging methods). Utility Model Content

[0005] According to one aspect of the present disclosure, a package is provided, comprising: a mounting substrate, at least one power chip attached to a first surface of the mounting substrate, the power chip comprising a power device; and a lead frame comprising a first chip attachment portion and at least one first lead, at least one cooperative device chip attached to the first chip attachment portion, the cooperative device chip comprising a cooperative device cooperating with the power device, wherein the heat generated by the cooperative device during normal operation is lower than that of the power device, wherein the at least one first lead is coupled to the first surface of the mounting substrate to be electrically connected to the power chip.

[0006] In some embodiments, the mounting substrate includes a first metal layer and a second metal layer and an insulating layer sandwiched between the first and second metal layers, the at least one power chip is attached to the surface of the first metal layer, the surface of the first metal layer serves as the first surface of the mounting substrate; and the lead frame includes metal.

[0007] In some embodiments, the lead frame further includes at least one second lead for electrically connecting to the outside of the package, and the at least one first lead, the first chip attach portion, and the at least one second lead are integrally formed.

[0008] In some embodiments, in the package, the heat dissipation performance of the lead frame is lower than the heat dissipation performance of the mounting substrate.

[0009] In some embodiments, the package is an IPM package, the mounting substrate includes one of the following: a DBC substrate, a DPC substrate, an AMB substrate, a DBA substrate or an IMS substrate; the power device includes one or more of the following: an IGBT, an IGET, an IGCT, a thyristor, a power Schottky diode; the cooperative device includes a diode.

[0010] In some embodiments, the first chip attach portion is disposed substantially flush with the first lead, or lower than the first lead.

[0011] In some embodiments, the at least one second lead is disposed higher than the first chip attach portion and the at least one first lead.

[0012] In some embodiments, the package also includes: a first wire, which is attached to the power chip and the cooperative device chip; and a molding compound, which at least encapsulates at least a portion of the mounting substrate, the power chip, the cooperative device chip, the first wire and at least a portion of the lead frame, wherein the molding compound exposes a second surface of the mounting substrate opposite to the first surface.

[0013] In some embodiments, the at least one first lead is disposed at an edge of the lead frame facing the at least one power chip, and the at least one first lead includes two or more first leads, wherein the two or more first leads are disposed to be evenly distributed at the edge.

[0014] In some embodiments, the package also includes: a controller chip for controlling the power device, wherein the controller chip is arranged on a second chip attachment portion of the lead frame and is electrically connected to the power chip through a second wire, the second chip attachment portion is separated from the first chip attachment portion and the at least one first lead, and the molding compound also encapsulates the second wire.

[0015] In some embodiments, the lead frame further includes a third lead separated from the first chip attach portion and the first lead for electrical connection to the outside, wherein the first wire is attached to the third lead.

[0016] According to another aspect of the present disclosure, an electrical system is further provided, which may include the package according to any embodiment.

[0017] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0019] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0020] Figure 1 A schematic diagram of an IPM package of the prior art is shown;

[0021] Figure 2 A schematic diagram of a package according to some embodiments of the present disclosure is shown;

[0022] Figure 3 A schematic diagram of a package according to some embodiments of the present disclosure is shown;

[0023] Figure 4 A schematic diagram of a package according to some embodiments of the present disclosure is shown;

[0024] Figure 5 shows a perspective schematic diagram of a package according to some embodiments of the present disclosure;

[0025] Figure 6 shows a schematic cross-sectional view of a package according to some embodiments of the present disclosure;

[0026] Figure 7 A schematic cross-sectional view showing a package according to other embodiments of the present disclosure; and

[0027] Figure 8 A flow chart of a packaging method according to some embodiments of the present disclosure is shown.

[0028] Note that in the embodiments described below, the same reference numerals are sometimes used in common between different drawings to represent the same parts or parts with the same functions, and their repeated descriptions are omitted. In this specification, similar reference numerals and letters are used to represent similar items, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0029] For ease of understanding, the positions, sizes, and ranges of various structures shown in the drawings and the like may not represent actual positions, sizes, and ranges, etc. Therefore, the disclosed technical solutions are not limited to the positions, sizes, and ranges disclosed in the drawings and the like. DETAILED DESCRIPTION

[0030] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure. In addition, techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and devices should be considered part of the authorized specification.

[0031] It should be understood that the following description of at least one exemplary embodiment is merely illustrative and does not constitute any limitation on the present disclosure and its application or use. It should also be understood that any implementation described exemplarily herein does not necessarily mean that it is preferred or advantageous over other implementations. The present disclosure is not limited by any stated or implied theory given in the above technical field, background technology, utility model content or specific implementation.

[0032] In addition, certain terms may also be used in the following description for reference purposes only and are not intended to be limiting. For example, the words "first", "second" and other such numerical words referring to structures or elements do not imply a sequence or order unless the context clearly indicates otherwise.

[0033] It should also be understood that when the term “include / comprises” is used in this document, it indicates the presence of the specified features, integers, steps, operations, units and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, units and / or components and / or their combinations.

[0034] As used herein, the term "chip" includes but is not limited to a die or a die.

[0035] Figure 1 FIG. 1 is a schematic top view of an IPM package of the prior art. It should be understood that some components in the figure are filled with shadows or patterns to distinguish them more clearly from other adjacent components.

[0036] like Figure 1 As shown, the IPM package 100 of the prior art includes a mounting substrate 11 and a lead frame 13. A power chip 111 and a cooperative device chip 113 cooperating with the power chip are attached to the mounting substrate 11. The mounting substrate 111 can be, for example, a DBC substrate to provide good heat dissipation. The DBC substrate can include a ceramic layer 101 and metal layers on both sides thereof. The figure shows a metal layer 103 on the ceramic layer 101. The metal layer can be formed of, for example, copper or a copper alloy. The power chip 111 and the cooperative device chip 113 are attached to the metal layer 103 and electrically connected thereto.

[0037] The power chip 111 may be provided with a power device (not shown), such as but not limited to an insulated gate bipolar transistor (IGBT). The cooperative device chip 113 may be provided with a cooperative device (not shown) that cooperates with the power device, such as but not limited to a diode (also called a freewheeling diode) connected in anti-parallel with the IGBT. As an example, three power chips 111 and three corresponding cooperative device chips 11 are shown in the figure. The cooperative device can be electrically connected to the power chip (power device) through, for example, a wire 115 to form a circuit.

[0038] The IMP package 100 can be divided into a power side (or power domain) and a control side (or control domain). Generally, the power side is provided with high voltage and large current, while the control side is provided with low voltage and current. Power devices and their cooperative devices are generally arranged on the power side. The controller for controlling the power devices is generally arranged on the control side.

[0039] The lead frame 13 may include metal, or may be formed of metal. The metal may be, for example, a copper alloy, including but not limited to binary, ternary, or quaternary copper-based alloys. The lead frame 13 may include a plurality of separate components. Figure 1 As shown, the lead frame 13 includes a plurality of leads 131 and 133. As shown in the figure, the leads 131 are attached to the metal layer 103 of the mounting substrate 101. The leads 133 are electrically connected to the corresponding power chip 111 and the cooperating device chip 113 through the wires 115.

[0040] The lead frame 13 may further include a chip attaching portion 135 on which a controller chip 139 is disposed. The controller chip 139 may provide a control signal to the power chip 111 through a wire 141. The lead frame 13 may further include a lead 137 for electrical and physical coupling of the controller chip 139 to the outside.

[0041] In the prior art design, both the IGBT and the diode are arranged on the DBC substrate to enhance their heat dissipation. In addition, the DBC substrate accounts for a considerable portion of the IPM packaging material cost (in some examples, up to 45%), which is the main factor affecting the IPM packaging cost.

[0042] The inventors of the present application have found that, for IPM packaging, heat is mainly generated by power devices. Furthermore, the inventors of the present application have proposed the solution disclosed herein after research. According to the embodiments of the present disclosure, the cost of the IPM package can be greatly reduced, and the heat dissipation requirements can still be met. According to the embodiments of the present disclosure, one or more problems of the IPM package of the prior art pointed out above are overcome. According to the embodiments of the present disclosure, the layout design of the DBC substrate can also be simplified.

[0043] Figure 2 Schematic diagrams of packages according to some embodiments of the present disclosure are shown. Figure 2 A top view of some components of the package (here, some components on the power side) is shown in FIG. Figure 2 In other top views, shadows or patterns are added to some of the illustrated components to better distinguish them from other components.

[0044] like Figure 2 As shown, the package 200 may include a mounting substrate 21 and a lead frame 23. At least one power chip 211 is attached to a first surface (2011, Figure 7 ). Preferably, the mounting substrate 21 is a multi-layer substrate. As an example, the mounting substrate 21 may include one of the following: a DBC substrate, a direct plated copper (DPC) substrate, an active metal braze (AMB) substrate, a direct bonding aluminum (DBA) substrate or an insulated metal substrate. As an example, Figure 2 The mounting substrate 21 may include a first metal layer 203 and a second metal layer 207 (see Figure 7 ) and an insulating layer 201 sandwiched between the first and second metal layers. In the DBC substrate, the insulating layer 201 can be formed of a ceramic material, and the metal layers 203 and 207 can be formed of copper. In other embodiments, the metal layer of the mounting substrate can be formed of, for example, copper or aluminum.

[0045] The first metal layer 203 on the ceramic layer 201 may have one or more partitions. Here, as an example, Figure 2 Two partitions 203_1 and 203_2 are shown, on which one or more power chips 211 are respectively arranged. The figure shows that three power chips 211 are arranged on the partition 203_1 of the first metal layer, and one power chip 211 is arranged on the partition 203_2. It should be understood that the first metal layer can have more or fewer partitions.

[0046] The power chip 211 may be attached to (and thus electrically connected to) the surface 2011 of the first metal layer 203 by solder (see Figure 7). The surface 2011 of the first metal layer 203 is also used as the first surface of the mounting substrate. The power chip may include power devices, such as one or more of the following: insulated gate bipolar transistors (IGBTs), injection enhanced gate transistors (IEGTs), integrated gate commutated thyristors (IGCTs), thyristors, power Schottky diodes, etc.

[0047] The lead frame 23 includes a metal, or in other words, the lead frame can be formed of a metal. As an example, the metal can contain copper, for example, copper or a copper-containing alloy; it should be understood that the present disclosure is not limited thereto. The lead frame 203 can include a first chip attachment portion 231 and at least one first lead 235. The cooperative device chip 233 is attached to the corresponding first chip attachment portion 231, respectively, for example, by soldering. The cooperative device chip includes a cooperative device that cooperates with the power device, for example, a diode. Take IGBT and a diode as an example of a power device and a cooperative device for explanation. In this case, the diode can be connected in an anti-parallel manner with the IGBT. When the IGBT is working (that is, a forward voltage is applied to the IGBT), a large current basically flows through the IGBT, and the freewheeling diode is cut off and does not work, so the heat is mainly generated by the power device (IGBT). When there is a large reverse electromotive force, the diode is turned on, guiding the current to pass through it, thereby protecting the power device (IGBT). Therefore, the heat generated by the cooperative device (diode) is lower than that of the power device (IGBT).

[0048] The first lead 235 is bonded to the first surface of the mounting substrate 21 (here, the upper surface 2011 of the metal layer 203) to be electrically connected to the power chip. The first lead 235 can extend outward from the edge of the first die attachment portion 231. Preferably, the edge of the first lead 235 is straight. The adjacent edges of the adjacent first leads 235 are each set to be straight and parallel to each other, and the gap between the adjacent edges is set to be equal width. Preferably, the first lead 235 is bonded to the mounting substrate 21 by laser welding or ultrasonic welding, so that the reliability of the bonding can be improved. The figure shows that six first leads 235 are bonded to the partition 203_1 of the first metal layer, and two first leads 235 are bonded to the partition 203_2 of the first metal layer. However, this is merely exemplary, and there may be more or fewer leads. In some embodiments, the lead frame 23 may also include additional leads, such as leads (second leads) 237, for example, for electrical connection to the outside of the package and / or other components.

[0049] As shown in the figure, a plurality of first leads 235 are arranged at the edge of the lead frame 23 facing the power chip, and are arranged to be evenly distributed at the edge. Thus, the first leads are also evenly distributed on the mounting substrate 21 (its metal layer 203). In this way, when the lead frame 23 is joined to the mounting substrate 21, the mounting substrate 21 is evenly stressed and not easily displaced or tilted, thereby improving or even eliminating the overflow of the molding compound to the back of the DBC substrate.

[0050] In addition, if Figure 2 As shown in the figure, the lead frame 23 may have a plurality of components separated from each other. As an example, a component 23_1, a component 23_2 and a plurality of other components 23_3 are shown in the figure. However, it should be understood that this is merely exemplary, for example, the lead frame 23 may have only a component 23_1 or a component 23_2, or may also have more components. As shown in the figure, the component 23_1 includes a chip attachment portion 231, a first lead 235 and a second lead 237. Preferably, the chip attachment portion 231, the first lead 235 and the second lead 237 are integrally formed. The component 23_2 is shown as being separated from the component 23_1, and includes a chip attachment portion 231, a first lead 235 and an additional lead (a second lead 237) for electrical connection with the outside and / or other components. In addition, other components, such as a component 23_3, are also shown in the figure, which may include an additional lead 239. Only the portion of component 23_3 including lead (third lead) 239 is schematically shown here, but it should be understood that component 23_3 may also include other parts, such as a chip attachment portion and / or a first lead that are arranged the same as or similar to components 23_1 and 23_2.

[0051] Here, it should also be understood that, although in this embodiment, the second lead 237 and the third lead 239 are shown and described as being used for electrical connection to the outside, the present disclosure is not limited thereto. For example, in other embodiments, the second lead 237 and the third lead 239 may not be electrically connected to the outside. In addition, it should also be understood that the configuration of the first lead, the second lead, and the third lead can be various, and the positions, sizes, shapes, quantities, etc. shown in the figure are all exemplary.

[0052] As shown in the figure, the wire (first wire) 251 is bonded to the power chip 211 and the cooperative device chip 233 to provide an electrical connection between the two. Although not shown here, it will be easily understood by those skilled in the art that a pad may be provided on the chip (e.g., a power chip, a cooperative device chip, and a controller chip to be described below), and a section of the wire may be bonded to the pad to provide a mechanical connection and an electrical connection. Preferably, the wire 251 is an aluminum wire; however, the present disclosure is not limited thereto, and for example, copper wire may also be used. As an example, one electrode of an IGBT chip (which serves as a power chip) may be electrically connected to the metal layer 203 (or a portion thereof) of the DBC substrate 21, and one electrode of a diode chip (which serves as a cooperative device chip) may be electrically connected to the lead frame 23 (or a component thereof, such as 23_1), so that the two are electrically connected to each other through the first lead. One end of the wire 251 may be electrically connected to another electrode of the IGBT chip, and the other part may be electrically connected to another electrode of the diode chip, so that an electrical connection is formed between the two. If necessary, the wire 251 may be further bonded to a corresponding second lead or other component, such as Figure 2 It should also be understood that although two wires 251 are shown for each power chip in the figure, the present disclosure is not limited thereto.

[0053] In the package, the mounting substrate such as the DBC substrate has excellent heat dissipation performance, but its price is also expensive, accounting for a considerable part of the cost of the IPM package. In the package, the heat dissipation performance of the lead frame is lower than that of the mounting substrate due to being encapsulated by the molding compound. For the application of IPM packaging and power devices, heat has a substantial impact on the performance of the power device and even the entire package. Therefore, heat dissipation is a particularly important consideration. In the prior art, there is always a tendency to place the electronic components on the power side on a mounting substrate with better heat dissipation (such as a DBC substrate) to meet the heat dissipation requirements, especially the higher the voltage and current that the power device tolerates.

[0054] The inventor of this application has carefully analyzed the heat dissipation of components in the prior art IPM package and realized that the cooperating device chip can be set at the lead frame while still meeting the heat dissipation requirements. In this way, the area of ​​the expensive mounting substrate such as the DBC substrate can be greatly reduced, thereby greatly reducing the cost of the package. In some examples, the size of the DBC substrate is reduced by up to 45.9%, and the module packaging cost is greatly reduced, while still maintaining the same heat dissipation effect of the packaged product.

[0055] For example, the size of the DBC substrate may be 29mm x 12mm x 0.98mm, the thickness of the lead frame may be 0.38mm, and the size of the IGBT chip may be 2.5mm x 2.5mm to 3.5mm x 4.8mm. The size of the diode chip may be 2.2mm x 2.2mm. According to the embodiment of the present disclosure, not only the part at the diode chip is eliminated, but also the IGBT chip can be as close to the first lead as possible.

[0056] In addition, since the power-side cooperative device chip is removed from the mounting substrate, the layout design of the mounting substrate is more flexible and simple. Moreover, due to the simplification of the layout of the mounting substrate, the size of the first lead can be designed to be smaller and the distribution more uniform, so that ultrasonic welding or laser welding can be used to join the lead (and lead frame) to the mounting substrate, reducing the connection failure rate between the lead frame and the mounting substrate and improving the reliability of the product.

[0057] Furthermore, compared to the prior art, in the embodiments of the present disclosure, the leads are more evenly distributed on the mounting substrate (eg, DBC substrate), thereby improving or eliminating the problem of overflow of the molding compound to the back side of the DBC.

[0058] Figure 3 A schematic top view of partial components of a package according to some embodiments of the present disclosure (here, including partial components on the power side and component portions on the control side) is shown. Figure 3 The package 300 shown substantially includes Figure 2 All components of the package 200 shown in FIG. 300 are shown in FIG. 300 . In addition, the device 300 also includes some components on the control side. Figure 3 As shown, the lead frame 23 may further include an additional component 23_5 for the control side, which is separated from other components 23_1, component 23_2, component 23_3, etc. The component 23_5 of the lead frame may include an additional die attach portion (second die attach portion) 301 and an additional lead (fourth lead) 331. The die attach portion (second die attach portion) 301 is also correspondingly separated from the first die attach portions 231 of the components 23_1 and 23_2 and their corresponding first leads 235.

[0059] The controller chip 303 is disposed on the chip attachment portion 301 and is electrically connected to the power chip through a wire (second wire) 311; thus, the controller chip 303 can provide a signal to the power chip to, for example, control the operation of the related power device. As an example, Figure 3 3 shows two chip attachment parts 301 and two controller chips 303. Preferably, the wire 311 can be a copper wire.

[0060] It should be understood that Figure 3 The configuration of the component 23_5 shown is merely exemplary; the present disclosure is not limited thereto. It should also be understood that the configuration of the third lead 331 can be varied. Figure 3 3 shows a plurality of different configurations of the third lead 331. Some of the leads 331 may be connected to the chip attachment portion 301, while the remaining leads 331 may be isolated from the chip attachment portion 301. Figure 3 Not shown, see Figure 6 601) electrically connects the control chip 303 to the corresponding leads isolated therefrom.

[0061] Those skilled in the art will readily appreciate that one or more of the above components 23_1, 23_2, 23_3, 23_5, etc. of the lead frame 23 may be connected by, for example, tie bars (not shown in the figure) in some intermediate products or intermediate manufacturing processes. The tie bars may be removed after applying the molding compound, thereby separating the above components from each other.

[0062] Figure 4 A schematic top view of a package according to some embodiments of the present disclosure is shown. Figure 4 The package shown essentially includes Figure 3 The package 300 shown in FIG. 1 includes all components of the package 300. The package further includes a mold compound 401. The mold compound 401 encapsulates at least a portion of the mounting substrate 21, the power chip 211, the cooperating device chip 233, the first wire 251, and at least a portion of the lead frame 23. In some embodiments, when a DBC substrate is used as the mounting substrate 21, the mold compound can be configured so that a second surface (2071, see FIG. 2071 ) of the mounting substrate 21 opposite to the first surface Figure 6 or Figure 7 ) exposed.

[0063] Figure 5 A perspective simulation view of a package according to some embodiments of the present disclosure is shown to aid understanding of the planar top view described above. Figure 5 The same components as those in the previous figures are denoted by the same reference numerals as those used in the previous figures, and thus their description will not be repeated here.

[0064] Figure 6 A schematic cross-sectional view of a package according to some embodiments of the present disclosure is shown. Figure 6 The same reference numerals are used for the same components as those in the previous figures, and therefore, they will not be described again here. Figure 6In the illustrated embodiment, the first chip attachment portion 231 is arranged to be substantially flush with the first lead 235, while the second lead 237 / third lead 239 is arranged to be higher than the corresponding first chip attachment portion 231. The lead 237 / 239 is arranged to be substantially flush with the lead 331 on the opposite side. In this way, the height of the cooperating device chip can be reduced (for example, relative to the bottom surface of the package), leaving sufficient clearance for forming the wire 251 thereon. In addition, the same lead configuration as the package of the prior art can be maintained.

[0065] Furthermore, since the first wire 251 protrudes above the mounting substrate 21 and the lead frame 23 , the thickness of the molding compound and the height of the first wire should be set so that the molding compound sufficiently covers the first wire (and other wires).

[0066] Figure 7 Schematic cross-sectional views of packages according to other embodiments of the present disclosure are shown. Figure 7 The same reference numerals are used for the same components as those in the previous figures, and therefore, they will not be described again here. Figure 7 In the illustrated embodiment, the first die attach portion 231 is further lowered and arranged to be lower than the first lead 235, while the lead 237 / 239 is arranged to be higher than both the first die attach portion 231 and the first lead 235. In this way, the height of the lead 251 can be further lowered, so that the height (thickness) of the molding compound can be correspondingly reduced. On the other hand, the cooperating device chip 233 can be made closer to the bottom surface of the package, thereby improving the heat dissipation of the cooperating device chip 233.

[0067] like Figure 6 and 7 As shown, the mounting substrate 21 may further include a second metal layer 207 disposed on an insulating layer (e.g., a ceramic layer) 201 opposite to the first metal layer 203. The first metal layer 203 and the second metal layer 207 are respectively disposed on both sides of the insulating layer 201. The molding compound 401 may be configured such that a surface 2071 of the second metal layer 207 is exposed. The molding compound also encapsulates the second wire 311, and other wires (e.g., a wire 601 from the control chip 303 to the lead 331).

[0068] Figure 8 FIG. 1 is a flow chart showing a method for preparing a package (or packaging method) according to some embodiments of the present disclosure. Figure 8 As shown, the method 800 includes, at step S801, attaching a power chip to the first surface of the mounting substrate, wherein the power chip includes a power device. For example, the power chip 211 may be attached to the first surface 2011 of the mounting substrate 21 by vacuum reflow soldering.

[0069] The method 800 further includes, at step S803, attaching a cooperative device chip to a first chip attachment portion of a lead frame, the lead frame further including at least one first lead. The cooperative device chip includes a cooperative device that cooperates with the power device, wherein the cooperative device generates less heat than the power device during normal operation. For example, the cooperative device chip 233 can be attached to the first chip attachment portion 231 of the lead frame 23 by soldering with a tin wire.

[0070] The method 800 further includes, at step S805, attaching the first lead to the first surface of the mounting substrate to electrically connect to the power chip. For example, the components of the lead frame can be supported by a mechanical support structure, such as a tie bar connecting the components of the lead frame, or a clip clamping the lead frame, and the first lead 235 is attached to the first surface 2011 of the mounting substrate 21 by laser welding or ultrasonic welding to electrically connect to the power chip 211.

[0071] The method 800 further includes, at step S807, performing wire bonding. Wire bonding includes bonding a first wire to the power chip and the cooperating device chip. For example, the first wire 251 may be bonded to the power chip 211 and the cooperating device chip 233 by aluminum wire bonding, thereby providing an electrical connection between the power chip 211 and the cooperating device chip 233. The first wire may be, for example, an aluminum wire.

[0072] The method 800 further includes, at step S809, applying a molding compound. For example, the molding compound 401 is applied to at least encapsulate at least a portion of the mounting substrate 21, the power chip 211, the cooperating device chip 233, the first wire 251, and at least a portion of the lead frame 23, such as Figure 4 , Figure 6 and Figure 7 shown.

[0073] In some embodiments, the tie bars between components of the lead frame may be removed after the molding compound is applied.

[0074] In some embodiments, the mounting substrate may include a first metal layer and a second metal layer and an insulating layer sandwiched between the first and second metal layers. The power chip is attached to a surface of the first metal layer, and the surface of the first metal layer serves as a first surface of the mounting substrate. The lead frame may include a metal, such as copper.

[0075] In some embodiments, the lead frame may further include at least one second lead, wherein the at least one first lead, the first die attach portion, and the at least one second lead are integrally formed. In some embodiments, the molding compound is further configured to expose a second surface of the mounting substrate opposite to the first surface.

[0076] In some embodiments, due to being encapsulated by the molding compound, the heat dissipation performance of the lead frame is lower than the heat dissipation performance of the mounting substrate. In some embodiments, the first chip attachment portion is arranged to be substantially flush with the first lead. In other embodiments, the first chip attachment portion is arranged to be lower than the first lead.

[0077] In some embodiments, the lead frame may include two or more first leads, the first leads being disposed at an edge of the lead frame facing the at least one power chip, and the two or more first leads being disposed to be evenly distributed at the edge.

[0078] In some embodiments, the lead frame further includes a third lead that is separate from the second die attach portion and the second lead, and wherein the first wire is also bonded to the third lead.

[0079] In some embodiments, the method 800 may further include, at step S806, attaching the controller chip to a second chip attach portion of the lead frame, the second chip attach portion being separated from the first chip attach portion and the first lead. For example, the controller chip 303 may be attached to the second chip attach portion 301 by silver adhesive bonding.

[0080] There is no particular limitation on the order of executing step S801, step S803 and step S806, as long as they are performed before the wire bonding step. For example, step S801 and step S803 can be performed at the same time, which can save the time required for the process flow. For another example, any one of step S801, step S803 and step S806 can be performed before the other two.

[0081] In some embodiments, wire bonding further includes bonding a second wire to the controller chip and the power chip. For example, copper wire or gold wire (second wire) 311 may be bonded to the controller chip 301 and the power chip 211 by copper wire or gold wire bonding. The molding compound 401 is also configured to encapsulate the second wire 311.

[0082] The present application also contemplates an electrical system, which may include the package according to any embodiment of the present disclosure. As an example, the electrical system may include, for example, an inverter, a new energy vehicle, a wind power system, a solar power generation system, an energy storage system, or any other device or system that requires the application of the package of the present disclosure.

[0083] The present disclosure also conceives the following items.

[0084] Item 1. A package, comprising: a mounting substrate, at least one power chip attached to a first surface of the mounting substrate, the power chip comprising a power device; and a lead frame comprising a first chip attachment portion and at least one first lead, at least one cooperative device chip attached to the first chip attachment portion, the cooperative device chip comprising a cooperative device cooperating with the power device, wherein the heat generated by the cooperative device during normal operation is lower than that of the power device, wherein the at least one first lead is coupled to the first surface of the mounting substrate to be electrically connected to the power chip.

[0085] Item 2. A package as described in Item 1, wherein: the mounting substrate includes a first metal layer and a second metal layer and an insulating layer sandwiched between the first and second metal layers, the at least one power chip is attached to the surface of the first metal layer, and the surface of the first metal layer serves as the first surface of the mounting substrate; and the lead frame includes metal.

[0086] Item 3. The package of Item 1, wherein: the lead frame further comprises at least one second lead for electrically connecting to the outside of the package, and the at least one first lead, the first chip attachment portion, and the at least one second lead are integrally formed.

[0087] Item 4. The package according to any one of Items 1 to 3, wherein: in the package, the heat dissipation performance of the lead frame is lower than the heat dissipation performance of the mounting substrate.

[0088] Item 5. A package as described in Item 1, wherein: the package is an IPM package, the mounting substrate includes one of the following: a DBC substrate, a DPC substrate, an AMB substrate, a DBA substrate or an IMS substrate; the power device includes one or more of the following: an IGBT, an IGET, an IGCT, a thyristor, a power Schottky diode; the cooperative device includes a diode.

[0089] Item 6. The package of Item 1, wherein the first chip attach portion is disposed to be substantially flush with the first lead or lower than the first lead.

[0090] Item 7. The package of Item 3, wherein: the at least one second lead is disposed higher than the first die attach portion and the at least one first lead.

[0091] Item 8. The package as described in Item 1 further includes: a first wire, which is attached to the power chip and the cooperative device chip; and a molding compound, which at least encapsulates at least a portion of the mounting substrate, the power chip, the cooperative device chip, the first wire and at least a portion of the lead frame, wherein the molding compound exposes a second surface of the mounting substrate opposite to the first surface.

[0092] Item 9. A package as described in Item 1, wherein: the at least one first lead is arranged at an edge of the lead frame facing the at least one power chip, and the at least one first lead includes two or more first leads, wherein the two or more first leads are arranged to be evenly distributed at the edge.

[0093] Item 10. The package as described in Item 8 further includes: a controller chip for controlling the power device, wherein the controller chip is arranged on a second chip attachment portion of the lead frame and is electrically connected to the power chip through a second wire, the second chip attachment portion is separated from the first chip attachment portion and the at least one first lead, and the molding compound also encapsulates the second wire.

[0094] Item 11. The package of Item 8, wherein the lead frame further includes a third lead separated from the first chip attach portion and the first lead for electrical connection to the outside, wherein the first wire is attached to the third lead.

[0095] Item 12. An electrical system comprising the enclosure of any one of Items 1-11.

[0096] Item 13. A method for preparing a package, comprising: attaching a power chip to a first surface of a mounting substrate, the power chip comprising a power device; attaching a cooperative device chip to a first chip attachment portion of a lead frame, the lead frame further comprising at least one first lead, the cooperative device chip comprising a cooperative device cooperating with the power device, wherein the heat generated by the cooperative device during normal operation is lower than that of the power device; attaching the at least one first lead to the first surface of the mounting substrate to be electrically connected to the power chip; performing wire bonding, the wire bonding comprising bonding a first wire to the power device and the cooperative device; and applying a molding compound to at least encapsulate at least a portion of the mounting substrate, the power chip, the cooperative device chip, the first wire, and at least a portion of the lead frame.

[0097] Item 14. A method as described in Item 13, wherein: the mounting substrate includes a first metal layer and a second metal layer and an insulating layer sandwiched between the first and second metal layers, the at least one power chip is attached to the surface of the first metal layer, the surface of the first metal layer serves as the first surface of the mounting substrate, the lead frame includes metal, the lead frame also includes at least one second lead, wherein the at least one first lead, the first chip attachment portion and the at least one second lead are formed integrally, and the molding compound is configured so that a second surface of the mounting substrate opposite to the first surface is exposed.

[0098] Item 15. The method of Item 13, wherein: when encapsulated by the applied molding compound, the lead frame has a lower thermal performance than the mounting substrate.

[0099] Item 16. The method of Item 13, wherein the first chip attach portion is disposed to be substantially flush with the first lead or lower than the first lead.

[0100] Item 17. A method as described in Item 13, wherein: the at least one first lead is arranged at an edge of the lead frame facing the at least one power chip, and the at least one first lead includes two or more first leads, wherein the two or more first leads are arranged to be evenly distributed at the edge.

[0101] Item 18. A method as described in Item 13, wherein the lead frame also includes a third lead, the third lead is separated from the second chip attachment portion and the second lead, and wherein the first wire is also bonded to the third lead, the method also includes: attaching a controller chip to the second chip attachment portion of the lead frame, the second chip attachment portion is separated from the first chip attachment portion and the first lead, wherein wire bonding also includes bonding the second wire to the controller chip and the power chip, wherein the molding compound also encapsulates the second wire.

[0102] Item 19. A method as described in Item 13, wherein: the package is an IPM package, the mounting substrate includes one of the following: a DBC substrate, a DPC substrate, an AMB substrate, a DBA substrate or an IMS substrate; the power device includes one or more of the following: an IGBT, an IGET, an IGCT, a thyristor, a power Schottky diode; the cooperative device includes a diode.

[0103] Those skilled in the art will appreciate that the boundaries between the operations (or steps) described in the above-described embodiments are merely illustrative. Multiple operations can be combined into a single operation, which can be distributed in additional operations, and the operations can be performed at least partially overlapping in time. Moreover, alternative embodiments may include multiple instances of specific operations, and the order of operations may be changed in other various embodiments. However, other modifications, variations, and replacements are equally possible. Therefore, this specification and accompanying drawings should be considered illustrative, not restrictive.

[0104] Although some specific embodiments of the present disclosure have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. The various embodiments disclosed herein may be combined in any manner without departing from the spirit and scope of the present disclosure. It should also be understood by those skilled in the art that various modifications may be made to the embodiments without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A package, characterized in that: include: a mounting substrate, at least one power chip attached to a first surface of the mounting substrate, the power chip including a power device; as well as a lead frame comprising a first chip attachment portion and at least one first lead, at least one cooperating device chip being attached to the first chip attachment portion, the cooperating device chip comprising a cooperating device cooperating with the power device, wherein the cooperating device generates less heat than the power device during normal operation, The at least one first lead is coupled to the first surface of the mounting substrate to be electrically connected to the power chip.

2. The package according to claim 1, wherein: in: The mounting substrate comprises a first metal layer, a second metal layer and an insulating layer sandwiched between the first and second metal layers, the at least one power chip is attached to a surface of the first metal layer, and the surface of the first metal layer serves as a first surface of the mounting substrate; and The lead frame includes metal.

3. The package according to claim 1, wherein: in: The lead frame further comprises at least one second lead for electrically connecting to the outside of the package, and The at least one first lead, the first die attach portion, and the at least one second lead are integrally formed.

4. The package according to any one of claims 1 to 3, characterized in that: in: In the package, the heat dissipation performance of the lead frame is lower than the heat dissipation performance of the mounting substrate.

5. The package according to claim 1, wherein: in: The package is an IPM package, The mounting substrate comprises one of the following: a DBC substrate, a DPC substrate, an AMB substrate, a DBA substrate or an IMS substrate; The power device includes one or more of the following: IGBT, IGET, IGCT, thyristor, power Schottky diode; The cooperating device comprises a diode.

6. The package according to claim 1, wherein: in, The first chip attach portion is configured as: substantially flush with the first lead, or below the first lead.

7. The package according to claim 3, characterized in that in: The at least one second lead is disposed higher than the first chip attach portion and the at least one first lead.

8. The package according to claim 1, wherein: Also includes: a first wire, the first wire being attached to the power chip and the cooperating device chip; as well as a molding compound that encapsulates at least a portion of the mounting substrate, the power chip, the cooperating device chip, the first wire, and at least a portion of the lead frame, The molding compound exposes a second surface of the mounting substrate opposite to the first surface.

9. The package according to claim 1, wherein: in: The at least one first lead is disposed at an edge of the lead frame facing the at least one power chip, and the at least one first lead includes two or more first leads, The two or more first leads are arranged to be evenly distributed at the edge.

10. The package according to claim 8, wherein: Also includes: A controller chip, used to control the power device, The controller chip is disposed on a second chip attachment portion of the lead frame and is electrically connected to the power chip through a second wire, and the second chip attachment portion is separated from the first chip attachment portion and the at least one first lead. The molding compound also encapsulates the second conductive line.

11. The package according to claim 8, wherein: in The lead frame further includes a third lead separated from the first chip attach portion and the first lead for electrical connection to the outside, wherein the first wire is attached to the third lead.

12. An electrical system, characterized in that: Comprising the package as claimed in any one of claims 1 to 11.

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