A lead protection part

Abstract

The present invention relates to the field of semiconductors and provides a lead protection member installed between a first mounting surface and a second mounting surface of a chip mounting frame, wherein there is a height difference between the first mounting surface and the second mounting surface; the lead protection member includes a support portion, the support portion includes a guide surface, a first side edge of the guide surface is in contact with the first mounting surface, and a second side edge of the guide surface extends toward the second mounting surface; compared with the prior art, the support portion is installed in the gap between the driver IC frame and the power chip frame, and is located below the lead passing through the gap, close to the lead; during injection molding, the support portion can be used to support and block the lead when the lead is impacted and collapses, to prevent the lead from contacting the driver IC side frame when collapsing and causing the lead to be pulled and damaged; the support portion includes an inclined guide surface to adapt to the wire routing path of the lead and provide better support.

Description

Technical Field

[0001] The present application relates to the field of semiconductors, and in particular to a lead protection component. Background Art

[0002] Intelligent Power Module (IPM), short for Intelligent Power Module, integrates a drive control IC and an inverter circuit consisting of an IGBT, FRD, or MOSFET. It is an advanced power switching device that combines the high current density, low saturation voltage, and high voltage resistance of GTRs (high-power transistors), with the high input impedance, high switching frequency, and low drive power of MOSFETs (field-effect transistors). Furthermore, IPMs integrate logic, control, detection, and protection circuits, making them easy to use. This not only reduces system size and development time, but also significantly enhances system reliability. This adapts to the current development trends of power devices—modularization, composites, and power integrated circuits (PICs), and is gaining increasing application in the power electronics field.

[0003] The packaging structure of IPM mainly consists of: chip, bonding material, lead frame, lead and plastic packaging material. Among them, the leads generally include gold wire, copper wire and aluminum wire. Since the chip pad of the driver IC is small and the current is small, gold wire / copper wire and gold wire lead connection are generally used, while aluminum wire is generally used for lead connection on the power side with larger current. Since the gold wire welding process is relatively mature, the lead connection on the driver IC side is mostly made of gold wire. The gold wire diameter is generally very small, and the commonly used wire diameters generally include 25um, 30um, 38um, and 42um. The connection between the driver IC and the power chip is also made with gold wire; in order to consider the heat dissipation problem, the power chip side frame generally needs to be close to the heat sink, so in most cases there will be a height difference between the driver IC side frame and the power chip side frame. The wire bonding process is followed by plastic encapsulation. The gold wires connecting the driver IC and the power chip will pass through the position with the aforementioned height difference. Since the wire diameter of the leads, especially the gold wires, is relatively thin, the leads at the above-mentioned position are very likely to be impacted during injection molding, resulting in displacement and deformation, or even breakage, thereby affecting the electrical function of the product. Summary of the Invention

[0004] The present invention provides a lead protection component to solve the problem in the prior art that the leads connecting the driver IC and the power chip are easily broken during injection molding.

[0005] A lead protection member is installed between a first mounting surface and a second mounting surface of a chip mounting frame, and there is a height difference between the first mounting surface and the second mounting surface; the lead protection member includes a supporting portion, and the supporting portion includes a guide surface, the first side of the guide surface is connected to the first mounting surface, and the second side of the guide surface extends toward the second mounting surface.

[0006] Preferably, the first mounting surface has a convex corner at the first side edge, and / or the guide surface has a concave corner covering the edge of the second mounting surface.

[0007] Preferably, it comprises a connecting portion, the connecting portion comprising a first end and a second end arranged opposite to each other; the first end of the connecting portion is connected to the supporting portion, and the second end of the connecting portion is detachably mounted on the chip mounting frame.

[0008] Preferably, the guide surface is an outwardly convex curved surface.

[0009] Preferably, the guide surface includes a first chamfer at its upper end and a second chamfer at its lower end.

[0010] Preferably, a plurality of baffles are installed at intervals on the guide surface; the baffles are used to prevent the deviation of the lead wire.

[0011] Preferably, the support portion is provided with a plurality of channels on a portion where no lead wire passes.

[0012] Preferably, the lead protection component is made of high-temperature resistant insulating material.

[0013] The present invention provides a chip firmware component, comprising: a chip mounting frame,

[0014] The chip mounting frame comprises:

[0015] a driver IC frame, to which the driver IC is fixed; the driver IC frame is located on the first mounting surface; and

[0016] A power chip frame, to which a power chip is fixed; the power chip frame is located on the second mounting surface that is sunken relative to the first mounting surface; and a gap is provided between the power chip frame and the driver IC frame;

[0017] The chip firmware component further includes the lead protection component; the lead protection component is installed relative to the gap.

[0018] Preferably, the first side of the supporting portion is butted against an end of the driver IC frame.

[0019] Preferably, the chip mounting frame is provided with a snap-fitting groove at a second end opposite to the connecting portion, and the second end is snap-fitted to the snap-fitting groove.

[0020] Preferably, the second end is interference fit with the snap-fit groove.

[0021] The present invention provides an intelligent power module, comprising:

[0022] The chip firmware component; and

[0023] The lead protection piece.

[0024] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0025] The support portion is installed in the gap between the driver IC frame and the power chip frame, and is located below the lead passing through the gap, close to the lead. During injection molding, the support portion can be used to support and block the lead when the lead is impacted and collapses, preventing the lead from contacting the driver IC side frame when collapsing, causing the lead to be pulled and damaged. The support portion includes an inclined guide surface to adapt to the lead's wire routing path and provide better support. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0028] Figure 1 This is a three-dimensional structural diagram of the lead protection component provided in this application.

[0029] Figure 2 This is a side sectional view of the lead protection member provided in this application.

[0030] Figure 3 A side sectional view of another embodiment of the lead protection member provided by the present application.

[0031] Figure 4 A three-dimensional structural diagram of the chip firmware component provided in this application.

[0032] Figure 5 A three-dimensional structural diagram of the chip mounting frame of the chip firmware assembly provided in this application.

[0033] Figure 6 This is a structural diagram of the gap between the driver IC frame and the power chip frame of the chip firmware component provided in this application.

[0034] Description of the drawings: 1-chip mounting frame, 101-driver IC frame, 102-power chip frame, 103-gap, 104-clip slot, 3-lead protection member, 301-connecting portion, 302-supporting portion, 303-baffle, 304-channel, 305-guide surface, 306-first chamfer, 307-second chamfer, 308-second surface, 309-third surface, 310-fourth surface, 311-first surface, 312-first side, 313-second side; X-length, Y-width, Z-height. DETAILED DESCRIPTION

[0035] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0036] The packaging structure of IPM mainly consists of: chip, bonding material, lead frame, leads and plastic packaging material. Among them, the leads generally include gold wire, copper wire and aluminum wire. Since the chip pad of the driver IC is small and the current is small, gold wire / copper wire and gold wire lead connection are generally used, while aluminum wire is generally used for lead connection on the power side with larger current. Due to the relatively mature gold wire welding process, the lead connection on the driver IC side is mostly made of gold wire. The gold wire diameter is generally very small, and the commonly used wire diameters generally include 25um, 30um, 38um, and 42um. The connection between the driver IC and the power chip is also made with gold wire; in order to consider the heat dissipation problem, the power chip side frame generally needs to be close to the heat sink, so in most cases there will be a height difference between the driver IC frame and the power chip frame. After the wire bonding process, the plastic packaging is carried out. The gold wires connecting the driver IC and the power chip will pass through the position with the height difference. Since the wires, especially the gold wires, are relatively thin, the wires at the above-mentioned position are easily impacted during the injection molding process, causing displacement and deformation, or even breakage, thereby affecting the electrical function of the product.

[0037] In order to solve the above technical problems, the present invention provides a lead protection part; the lead protection part is installed in the gap between the driver IC frame and the power chip frame; during injection molding, the lead protection part located in the gap can provide support for the lead, thereby preventing the lead at the above position from being impacted and causing displacement and deformation, or even breakage.

[0038] See also Figures 1 to 6 , Figure 1 A three-dimensional structural diagram of the lead protection member provided in this application; Figure 2A side cross-sectional view of the lead protection member provided in this application; Figure 3 A side cross-sectional view of another embodiment of the lead protection member provided by the present application; Figure 4 A three-dimensional structural diagram of the chip firmware component provided in this application; Figure 5 A three-dimensional structural diagram of the chip mounting frame of the chip firmware component provided in this application; Figure 6 This is a structural diagram of the gap between the driver IC frame and the power chip frame of the chip firmware component provided in this application.

[0039] The present invention provides a lead protection member, which is installed between a first mounting surface and a second mounting surface of a chip mounting frame 1, and there is a height difference between the first mounting surface and the second mounting surface; the lead protection member includes a support portion 302, and the support portion 302 includes a guide surface 305, a first side 312 of the guide surface 305 is connected to the first mounting surface, and a second side 313 of the guide surface 305 extends toward the second mounting surface, the first mounting surface has an outward convex corner at the first side 312, and / or the guide surface 305 has an inward concave corner covering the edge of the second mounting surface.

[0040] The first mounting surface is provided with a driver IC frame 101, and the second mounting surface is provided with a power chip frame 102; the driver IC is mounted on the driver IC frame 101, and the power chip is mounted on the power chip frame 102; the support portion 302 of the lead protection member is mounted in the gap 103 between the driver IC frame 101 and the power chip frame 102; the upper end of the support portion 302 is docked with the end of the driver IC frame 101; the lead 4 refers to the lead connecting the driver IC and the power chip; the support portion 302 is located below the lead 4; the support portion 302 includes a guide surface 305, because the guide surface 305 is along the The routing direction of the lead 4 is set, when injection molding, the part of the lead 4 located in the gap 103 will move downward when it is subjected to the impact force of the injection molding material; the support portion 302 provides support to prevent the lead 4 from moving downward, and can prevent the lead 4 from contacting the positive corner of the edge of the driver IC frame 101, thereby preventing the lead 4 from being pulled by the edge of the driver IC frame 101 due to excessive displacement, and also avoiding the lead 4 from being damaged by pulling; further, in one embodiment, the second side 313 of the guide surface 305 is connected to the second mounting surface, that is, the second side 313 of the guide surface 305 can be connected to the power chip frame 102.

[0041] The lead 4 described in the present invention includes gold wire, copper wire and aluminum wire. Since the chip pad of the driver IC is small and the current is small, gold wire / copper wire and gold wire lead connection are generally used, while aluminum wire is generally used for lead connection on the power side with larger current; in the present invention, considering that copper is easily oxidized, the present invention preferably uses gold wire; those skilled in the art can also choose leads of other materials according to actual needs.

[0042] like Figure 2 As shown, the supporting portion 302 includes a first surface 311, a second surface 308, a third surface 309, a fourth surface 310 and the guide surface 305; in actual use, the first surface 311 and the driver IC frame 101 are located in the same plane; the third surface 309 is located below the first surface 311 and parallel to the first surface 311, and the width of the third surface 309 is greater than the width of the first surface 311; the second surface 308 connects the first surface 311 and the third surface 309; the second surface 308 is perpendicular to the first surface 311 and the third surface 309; the fourth surface 310 on the other side is parallel to the second surface 308; the lower end of the fourth surface is connected to the third surface 309; the upper and lower ends of the guide surface 305 are connected to the end of the first surface 311 and the upper end of the fourth surface 310; the front end of the first surface 311 is docked with the end of the driver IC frame 101.

[0043] In one embodiment, Figure 2 As shown, the guide surface 303 may be a straight inclined surface; the angle of the inclined surface is set relative to the routing direction of the lead 4 connecting the driver IC and the power chip.

[0044] In order to prevent the positive angle of the support portion 302 from damaging the lead 4, in one embodiment, Figure 3 As shown, the upper end and the lower end of the guide surface 305 are respectively provided with a first chamfer 306 and a second chamfer 307 .

[0045] In order to improve the protection and support function of the support portion 302 on the lead 4, in one embodiment, the guide surface 305 is configured as an outwardly convex curved surface (not shown in the figure).

[0046] Furthermore, the width y of the support portion 302 is equal to the width of the gap 103 between the power chip frame 102 of the chip mounting frame 1 and the driver IC frame 101; the height Z of the support portion 302 is less than or equal to the height difference between the driver IC frame 101 and the power chip frame 102; and the length X of the support portion 302 is less than or equal to the length of the gap 103.

[0047] Preferably, the lead protection member also includes a connecting portion 301, and the connecting portion 301 includes a first end and a second end arranged opposite to each other; the first end of the connecting portion 301 is connected to the supporting portion 302, and the second end of the connecting portion is detachably mounted on the chip mounting frame 1; the connecting portion 301 and the supporting portion 302 can be integrally formed; in other embodiments, the connecting portion 301 can be detachably mounted on both ends of the supporting portion 302; the detachable installation can be a bolt installation or a snap-on connection; it should be understood that for the above-mentioned detachable connection between the connecting portion 301 and the supporting portion 302, those skilled in the art can also use other known detachable connection methods.

[0048] Preferably, the lead protection member is made of a high-temperature resistant insulating material;

[0049] In one embodiment, the high-temperature resistant insulating material can be made of polytetrafluoroethylene, which is a polymer made by polymerizing tetrafluoroethylene as a monomer. It is white, waxy, translucent, insulating, heat-resistant, and cold-resistant, and can be used for a long time at -180 to 260°C. This material is resistant to acids, alkalis, and various organic solvents, and is almost insoluble in all solvents. The high-temperature resistant insulating material can also be made of other high-temperature resistant insulating polymers, such as polyphenylene, polyparaxylene, polyarylether, polyarylate, aromatic polyamide, polyimide, polybenzimidazole, polyquinoline, polypyrrole, graphite ladder polymer, phenanthroline ladder polymer, and quinoline ladder polymer. Organic polymers containing silicon, phosphorus, and boron in the main chain, other organometallic polymers, and inorganic polymers can also be used.

[0050] In one embodiment, the high-temperature insulating material can be a ceramic material, such as alumina ceramic or aluminum nitride ceramic. Alumina ceramic is a ceramic material with aluminum oxide (Al2O3) as its primary crystalline phase. Its advantages include excellent thermal conductivity and insulation, relatively low high-frequency loss, and good high-frequency insulation. Its Rockwell hardness reaches HRA80-90, which is only second to diamond and far exceeds the wear resistance of wear-resistant steel and stainless steel. The wear resistance of alumina ceramic is equivalent to 266 times that of manganese steel and 171.5 times that of high-chromium cast iron. Under equivalent operating conditions, it can extend the service life of equipment by at least ten times. Using alumina ceramic as an insulating substrate can effectively extend the service life of power modules. Alumina ceramic has a density of only 3.5g / cm3, only half that of steel. Using it as an insulating substrate for power modules can significantly reduce the overall weight of the device. The aluminum nitride ceramic is a ceramic material with aluminum nitride (AIN) as the main crystal phase. It has excellent comprehensive performance and a theoretical thermal conductivity of 320W / (m). Compared with other ceramic materials, it has better thermal conductivity. Its use in the insulating substrate of the power module can improve the heat dissipation performance of the power module and increase the service life of the chip of the power module, thereby increasing the service life of the power module. In addition to having excellent conductivity, the aluminum nitride ceramic also has reliable electrical insulation, low dielectric constant and loss, non-toxicity, and a thermal expansion coefficient matching that of silicon. The high-temperature resistant insulating material can also be selected from other inorganic materials, such as glass fiber, mica and other inorganic insulating and high-temperature resistant materials.

[0051] It should be understood that the above-mentioned high-temperature resistant insulating material is only one or several specific embodiments, and other high-temperature resistant insulating materials in the prior art should all fall within the scope of protection of this patent.

[0052] During the injection molding process, the lead 4 is easily deflected to both sides under the impact of the injection molding material. The above situation easily causes multiple leads 4 to overlap or tangle together, thereby affecting the normal operation of the chip. In order to solve the above technical problems, as Figure 1As shown, a plurality of baffles 303 are installed at intervals on the guide surface 305; the baffles 303 are used to prevent the deviation of the leads 4; the baffles 303 are perpendicular to the guide surface 305; further, the number of the baffles 303 is set according to the number of the leads 4 connecting the power chip and the driver IC; further, the baffles 303 can be integrally formed with the support portion 302; the baffles 303 can also be detachably installed on the support portion 302; the detachable installation method can be installed by bolts; or it can be installed by corresponding clamping of a slider and a slide groove. Specifically, a plurality of slide grooves are provided on the guide surface 305, and the two ends or one end of the slide grooves are open. The slide grooves can be set as dovetail grooves or T-slots, and a slider can be provided on the lower part of the baffle 303 corresponding to the slide groove; it should be understood that for the detachable connection method of the baffle 303 and the support member 302, those skilled in the art can also adopt other types of known detachable connection structures.

[0053] like Figure 1 As shown, the support portion 302 is provided with a plurality of channels 304, and the function of the channels 304 is to facilitate the flow and filling of the resin; in order to prevent the lead 4 from being pressed into the channel 304 by the resin, the channels 304 are all arranged on the portion of the support portion 302 where the lead 4 does not pass; it should be understood that the present invention does not limit the axial direction of the channel 304 and the cross-sectional shape of the channel 304.

[0054] The present invention also provides a chip firmware assembly, comprising: a chip mounting frame 1, wherein the chip mounting frame 1 includes mounting positions for mounting the driver IC and the power chip. The chip mounting frame 1 includes:

[0055] A driver IC frame 101, to which the driver IC is fixed; the driver IC frame 101 is located on the first mounting surface; and

[0056] A power chip frame 102, to which a power chip is fixed; the power chip frame 102 is located on a second mounting surface that is sunken relative to the first mounting surface; a gap 103 is provided between the power chip frame 102 and the driver IC frame 101;

[0057] The chip firmware component further includes the lead protection component; the lead protection component is installed relative to the gap 103.

[0058] Preferably, the first side 312 of the supporting portion 302 is butted against an end of the driver IC frame 101 .

[0059] The connecting portion 301 of the lead protection member is mounted on the chip mounting frame 1 by snap-fitting. Preferably, Figure 5 As shown, the chip mount 1 has a snap-fit groove 104 opposite the second end, and the second end of the connecting portion 301 is snap-fitted to the snap-fit groove 104. In one embodiment, the connecting portion 301 is mounted to the chip mount 1 via an interference fit between its second end and the snap-fit groove 104. The connecting portion 301 can also be mounted to the chip mount 1 via bolts. Those skilled in the art can also mount the lead protector to the chip mount 1 using other known detachable connection methods.

[0060] The lead protection member may also be integrally formed with the chip mounting frame 1 .

[0061] The present invention also provides an intelligent power module, comprising:

[0062] The chip firmware component; and

[0063] The lead protection piece.

[0064] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0065] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein, but is intended to be embodied in the widest possible manner consistent with the principles and novel features claimed herein.

Claims

1. A lead protection member, characterized in that: The lead protection member is mounted between a first mounting surface and a second mounting surface of a chip mounting frame (1), wherein there is a height difference between the first mounting surface and the second mounting surface; the lead protection member comprises a support portion (302), the support portion (302) comprises a guide surface (305), a first side edge (312) of the guide surface (305) is in contact with the first mounting surface, and a second side edge (313) of the guide surface (305) extends toward the second mounting surface; the support portion (302) comprises a first surface (311), a second surface (312), and a second surface (313). 08), the third surface (309), the fourth surface (310) and the guide surface (305), the driver IC frame (101) on the first mounting surface, the first surface (311), the guide surface (305) and the fourth surface (310) are connected in sequence, the upper end and the lower end of the guide surface (305) are connected to the end of the first surface (311) and the upper end of the fourth surface (310); the front end of the first surface (311) is docked with the end of the driver IC frame (101) on the first mounting surface; The lead protection member comprises a connecting portion (301), wherein the connecting portion (301) comprises a first end and a second end arranged opposite to each other; the first end of the connecting portion (301) is connected to the supporting portion (302), and the second end of the connecting portion (301) is detachably mounted on a chip mounting frame (1).

2. The lead wire protector according to claim 1, wherein: The first mounting surface has an outward convex corner at the first side edge (312), and / or the guide surface (305) has an inward concave corner covering the edge of the second mounting surface.

3. The lead wire protector according to claim 1, wherein: The width (y) of the support portion (302) is equal to the width of the gap (103) between the power chip frame (102) of the chip mounting frame (1) and the driver IC frame (101); the height (Z) of the support portion (302) is less than or equal to the height difference between the driver IC frame (101) and the power chip frame (102); and the length (X) of the support portion (302) is less than or equal to the length of the gap (103).

4. The lead wire protector according to claim 1, wherein: The guide surface (305) is an outwardly convex curved surface.

5. The lead wire protector according to claim 1, wherein: The guide surface (305) includes a first chamfer (306) at its upper end and a second chamfer (307) at its lower end.

6. The lead wire protector according to claim 1, wherein: A plurality of baffles (303) are installed at intervals on the guide surface (305); the baffles (303) are used to prevent the lead wire (4) from deflecting.

7. The lead wire protector according to claim 1, wherein: The support portion (302) is provided with a plurality of channels (304) on a portion where no lead wire (4) passes.

8. The lead protection member according to any one of claims 1 to 7, characterized in that: The lead protection component is made of high-temperature resistant insulating material.

9. A chip firmware component, comprising: Chip mounting frame (1), The chip mounting frame (1) comprises: a driver IC frame (101), the driver IC being fixed to the driver IC frame (101); the driver IC frame (101) being located on the first mounting surface; and A power chip frame (102), a power chip being fixed to the power chip frame (102); the power chip frame (102) being located on the second mounting surface that is sunken relative to the first mounting surface; and a gap (103) being provided between the power chip frame (102) and the driver IC frame (101); The chip firmware component further comprises a lead protection member according to any one of claims 1 and 5-8; the lead protection member is installed relative to the gap (103).

10. The chip firmware component according to claim 9, characterized in that: The first side edge of the support portion (302) is butted against the end of the driver IC frame (101).

11. The chip firmware component according to claim 10, characterized in that: The second end of the chip mounting frame (1) opposite to the connecting portion (301) is provided with a snap-in slot (104), and the second end is snap-into the snap-in slot (104).

12. The chip firmware component according to claim 11, characterized in that: The second end is interference-fitted with the snap-fitting groove (104).

13. An intelligent power module, comprising: The chip firmware component according to any one of claims 9 to 12; as well as, The lead protection member according to any one of claims 1 to 8.

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