Compact direct bond metal substrate package

Abstract

A compact power inverter (100, 400, 450) is effectively disposed on a multi-layer direct bond metal (DBM) structure (102), which occupies a reduced area and has a straight short-range extended wire bond (107, 407, 457). The compact layout reduces the amount of material required to fabricate the multilayer DBM (102) including the silicon nitride ceramic layers (102b, 402b). The layout is also designed such that the wire bonds (107, 407, 457) can be routed without bending around the corners. The compact DBM structure (102) and short wire bonds (107, 407, 457) provide a low cost and highly reliable solution.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the benefit of U.S. patent application No. 18 / 353,148, filed on July 17, 2023, and entitled “Compact Direct-Bonded Metal Substrate Package,” which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to assembling and packaging semiconductor device modules, semiconductor device assemblies, and semiconductor devices. More particularly, the present invention relates to semiconductor device modules in which components are arranged in a compact layout. Background Art

[0004] A semiconductor device assembly (e.g., a chip assembly including a power semiconductor device) can be implemented using multiple semiconductor dies, substrates (e.g., die attach pads (DAPs)), electrical interconnects, and molding compounds. Power transistors can include, for example, insulated gate bipolar transistors (IGBTs), power metal oxide semiconductor field effect transistors (MOSFETs), and the like. Fast recovery diodes (FRDs) can be used in conjunction with power transistors. Electrical interconnects within a high-power semiconductor device module can include, for example, bonding wires, conductive spacers, and conductive clips. Polymer molding compounds can be used as encapsulants to protect components of the device assembly. Such high-power chip assemblies packaged as semiconductor device modules can be used in a variety of applications, including electric vehicles (EVs), hybrid electric vehicles (HEVs), and industrial applications. Summary of the invention

[0005] In some aspects, the technology described herein relates to a device comprising: a substrate; a lead frame attached to the substrate and having a gate lead frame post, a sense lead frame post, and a ground connection; a direct bond metal (DBM) structure located on the substrate and comprising a silicon nitride-based ceramic layer; a first die and a second die attached to the DBM structure in parallel; a U-shaped metal clip coupling the top sides of the first die and the second die to the lead frame using solder; and a wire bond directly coupling the gate terminals of the first die and the second die to the gate lead frame post.

[0006] In some aspects, the technology described herein relates to an apparatus that also includes wire bonds coupling a sense terminal of the second die to the sense leadframe post.

[0007] In some aspects, the technology described herein relates to an apparatus that also includes an arm of a metal clip that couples a sense terminal of a second die to a sense lead frame post.

[0008] In some aspects, the technology described herein relates to an apparatus in which a metal clip is connected to a ground connection.

[0009] In some aspects, the technology described herein relates to a device, the device comprising: a substrate; a lead frame portion, the lead frame portion being located on the substrate; a direct bond metal (DBM) structure, the DBM structure being located on the substrate and comprising a first metal layer, a second metal layer, and a ceramic layer disposed between the first metal layer and the second metal layer, a die pad and a gate pad defined in the first metal layer; a first die and a second die, the first die and the second die being attached to the die pad of the DBM substrate in parallel;

[0010] In some aspects, the technology described herein relates to a U-shaped metal clip having a first tab coupled to a top side of a first die and having a second tab coupled to a top side of a second die, the U-shaped metal clip having a third tab coupled to a lead frame portion (on opposite ends of the first and second tabs of the U-shaped metal clip); and a wire bond comprising a first wire bond coupling a gate terminal of the first die to a gate terminal of the second die, and a second wire bond coupling the second die to a gate pad.

[0011] In some aspects, the technology described herein relates to an apparatus that also includes another wire bond coupling a sense terminal of a second die to the sense lead frame post.

[0012] In some aspects, the technology described herein relates to an apparatus wherein the wire bonds further include a third wire bond that couples the gate pad to the gate leadframe post.

[0013] In some aspects, the technology described herein relates to an apparatus wherein a first wire bond extends in a lateral direction relative to a gate leadframe post.

[0014] In some aspects, the technology described herein relates to a device wherein the length dimension and the width dimension of the DBM are each less than 15 mm.

[0015] In some aspects, the technology described herein relates to a device wherein the wire bonds are made of 300 μm aluminum wire.

[0016] In some aspects, the technology described herein relates to a device in which the first die and the second die include silicon carbide (SiC).

[0017] In some aspects, the technology described herein relates to a method comprising: attaching the back side of a first die and a second die to a direct bond metal (DBM) structure; forming a lead frame and a metal clip; attaching the DBM structure to a substrate; attaching the metal clip between the top side of the first die and the second die and a ground plate of the lead frame; coupling the gate terminals of the first die and the second die to a first lead frame column; and coupling the sense terminal of the second die to a second lead frame column.

[0018] In some aspects, the technology described herein relates to a method wherein coupling a gate terminal to a first leadframe column includes using a wire bond.

[0019] In some aspects, technology described herein relates to a method wherein coupling a gate terminal to a first leadframe column includes directly coupling a gate terminal of a first die to a gate terminal of a second die and coupling the gate terminal of the second die to the first leadframe column.

[0020] In some aspects, the technology described herein relates to a method in which coupling a gate terminal of a second die to a first leadframe column includes coupling the gate terminal of the second die to a gate pad and coupling the gate pad to the first leadframe column.

[0021] In some aspects, the technology described herein relates to a method wherein coupling the sense terminal to the second lead frame post includes using a wire bond.

[0022] In some aspects, technology described herein relates to a method wherein coupling the sense terminal to the second lead frame post includes using a tab of a metal clip.

[0023] In some aspects, technology described herein relates to a method wherein forming a metal clip includes forming the metal clip from copper.

[0024] In some aspects, technology described herein relates to a method in which forming a leadframe includes forming the leadframe from copper.

[0025] In some aspects, the technology described herein relates to a method that also includes encapsulating the substrate in a package, wherein a backside of the package exposes an underlying layer of the DBM structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a perspective view of a compact power module according to a first embodiment of the present disclosure.

[0027] Figure 2 According to the embodiments of the present disclosure Figure 1 Top plan view of the compact power module shown.

[0028] Figure 3 According to the embodiments of the present disclosure Figure 1 Rear plan view of the compact power module shown.

[0029] Figure 4A is a perspective view of a compact power module according to a second embodiment of the present disclosure.

[0030] Figure 4B is a perspective view of a compact power module according to a third embodiment of the present disclosure.

[0031] Figure 5A and Figure 5B According to the embodiments of the present disclosure Figure 4A and Figure 4B Top plan view of the compact power module shown.

[0032] Figure 6 is a rear plan view of a compact power module according to an embodiment of the present disclosure.

[0033] Figure 7 is a flow chart illustrating a method of manufacturing a compact power module according to an embodiment of the present disclosure.

[0034] When with Figure 1 When reading together, the various aspects of the present disclosure are best understood from the following detailed description. It should be noted that, according to the convention in the industry, various features are not necessarily drawn to scale. For the clarity of discussion, the sizes of various features may be increased or reduced arbitrarily. In the accompanying drawings, the same reference symbol may indicate the same and / or similar parts (elements, structures, etc.) in different views. The accompanying drawings generally illustrate various embodiments discussed in the present disclosure by way of example and not limitation. The reference symbols shown in one figure may not be repeated for the same and / or similar elements in the related views. The reference symbols repeated in multiple figures may not be specifically discussed with respect to each of the figures in these figures, but are provided for the context between the related views. In addition, not all similar elements in the drawings are specifically referenced with reference symbols when multiple instances of the element are shown. DETAILED DESCRIPTION

[0035] The area occupied by electronic devices is important for material cost and reliability. When electronic devices are laid out in an inefficient manner, wasted space on the substrate adds unnecessary material cost. In addition, the wiring between the spaced-apart devices may be inherently more susceptible to damage or breakage, and thus may cause reliability failures to occur. These concerns are particularly important for high-performance semiconductors that include expensive materials such as silicon carbide (SiC), silicon nitride (SiN), and silicon nitride (SiC). 3 N 4) and direct bonded metal (DBM) structures such as direct bonded copper (DBC) structures are particularly important. When these high-power modules are manufactured in large quantities, even a slight reduction in the cost per unit can save a lot of money in the millions of dollars.

[0036] The present disclosure relates to implementing a compact power inverter that is efficiently laid out on a multi-layer DBC structure, has a reduced footprint and has wire bonds that extend over a short distance. Although the entire package may be larger, the compact DBC structure and short wire bonds provide a low-cost and highly reliable solution. Since design and process changes may exceed the cost savings of less, relatively cheap plastic material required for a smaller package, shrinking the injection molded package may also be cost-effective. Therefore, a compact power inverter can be accommodated in a package that appears to be oversized. Although the embodiments described herein relate to the packaging of circuits associated with power inverters, other types of circuits may be included in the packaging configurations described herein.

[0037] Figure 1 is a perspective view of a high-power semiconductor device module or compact power module 100 according to a first embodiment of the present disclosure. In some embodiments, the compact power module 100 includes a high-power semiconductor chip assembly or a compact electronic power assembly 101. The compact electronic power assembly 101 includes a single-sided direct bond metal (DBM) structure 102, a die attach pad (DAP) 102a, and one or more electronic components such as semiconductor dies or chip assemblies 104 (two are shown). The chip assembly 104 is attached to (e.g., mounted on or coupled to) the top surface of the die attach pad 102a by a bonding agent (e.g., epoxy, solder, silver (Ag) sintering material and / or adhesive). In some embodiments, the compact electronic power assembly 101 operates at 650 volts and 200 amperes.

[0038] In some embodiments, the DBM structure 102 can be a direct bond copper (DBC) type structure, a direct electroplated copper (DPC) type structure, or a direct bond aluminum (DBA) type structure. The DBM structure 102 can be referred to as a heat sink, which can perform single-sided cooling or double-sided cooling of the compact electronic power component 101. In some embodiments, the thickness of the DBM structure 102 is in the range of about 0.5 mm to about 3.0 mm. In some embodiments, the direct bond metal (DBM) structure 102 is designed as a three-layer DBM structure, which includes an upper metal layer and a lower metal layer separated by a dielectric layer. In some embodiments, the dielectric layer acts as a thermal mass disposed between two outer metal layers to absorb and absorb heat. The dielectric layer can also electrically insulate the upper metal layer from the lower metal layer of the DBM structure. In some embodiments, the dielectric layer can be a ceramic, such as silicon nitride (Si 3 N 4 ) or aluminum oxide (Al 2 O 3 ), Si 3 N 4 is better than Al 2 O 3 Significantly more expensive ceramic material.

[0039] The central region of the compact electronic power assembly 101 includes a die attach pad (DAP) 102a to which the chip assembly 104 is mounted. In some embodiments, the die attach pad 102a may be formed by an upper metal layer of the DBM structure 102. Figure 2 As shown, the die attach pad 102a may include a cutout, for example on the right side, to accommodate a landing pad for connecting a wire bond. In some embodiments, the dielectric layer and / or bottom metal layer of the DBM may have a larger footprint than the die attach pad 102a.

[0040] In some embodiments, the chip assembly 104 may include, for example, an iGBT (transistor) semiconductor die as shown on the left and an FRD (diode) semiconductor die as shown on the right. However, other types of semiconductor dies may be used as one or more chip assemblies in the chip assembly 104 in the compact electronic power assembly 101. In some embodiments, the term "chip assembly 104" may refer to a single semiconductor die. The chip assembly 104 may be manufactured on various types of semiconductor substrates (e.g., semiconductor wafers, such as silicon (Si), silicon carbide (SiC), gallium (Ga), gallium nitride (GaN), aluminum gallium nitride (AlGaN), gallium arsenide (GaAs), aluminum gallium arsenide (AlGaAs), indium phosphide (InP), glass substrates, sapphire substrates, etc.). In some embodiments, the chip assembly 104 may be manufactured on different substrates. For example, the iGBT chip assembly 104a may be manufactured on the silicon substrate of the semiconductor die 104a, while the FRD chip assembly 104b may be manufactured on the SiC substrate. In some embodiments, the chip assembly 104 is manufactured on the SiC substrate.

[0041] In some embodiments, the compact power module 100 further includes a U-shaped clip 105, a lead frame 106, wire bonds 107 (four are shown), an island 108, a mounting bracket plate 109, and a mounting bracket 112 (which may be a lead frame extension or may be part of the lead frame in some embodiments). In some embodiments, the lead frame 106, the U-shaped clip 105, the mounting bracket 112, and the lead posts 114 and 116 may be cut or stamped from a rolled sheet of metal such as copper.

[0042] The U-clip 105 couples the chip assembly 104 directly to the lead frame 106. The U-clip 105 provides mechanical and electrical connections to the terminals of the diode and transistor devices on the chip assembly 104. The U-clip 105 also serves to dissipate heat from the chip assembly 104. In some embodiments, the U-clip 105 may include tabs 103 (two are shown) separated by a break. The tabs 103 may extend from the body of the U-clip 105 along the longitudinal direction of the compact power module 100, such as aligned with the y-axis (between the mounting bracket 112 and the lead frame 106) to provide separate connections to different terminals of the devices within the IGBT chip assembly 104. In some embodiments, the U-clip 105 may be contoured to conform to a horizontal plane that steps up from the lead frame 106, across the DBM 102, and then steps down to the chip assembly 104. The profile of the U-clip 105 is spaced apart from the DBM structure 102 such that the U-clip 105 and the die attach pad 102 a do not make physical or electrical contact.

[0043] Wire bonds 107 couple the semiconductor devices on chip assembly 104 directly to or via island 108 to lead posts 114 and 116. In some embodiments, wire bonds 107 are made of aluminum wire having a diameter of 300 μm. Island 108 may be located in a cutout formed by the boundary of die attach pad 102a. The cutout creates a DBM in which the shape of die attach pad 102a may resemble a U-shape (e.g., a tab of U-clip 105) in a direction orthogonal to the shape of U-clip 105. Lead posts 114 and 116 provide a signal path from packaged compact electronic power assembly 101 to external devices, power, and ground connections.

[0044] The mounting bracket 112 may be used to mount the compact power module 100 to a heat sink (not shown). The mounting bracket plate 109 provides a mechanical coupling between the mounting bracket 112 and the DAP 102a. Due to the compact size of the DBM structure 102, the mounting bracket plate 109 may be elongated (or have an elongated shape) to traverse the increased distance between the mounting bracket 112 and the DBM structure 102. In some embodiments, the mounting bracket plate 109 may extend upward to about half the length of the encapsulant 110. The mounting bracket plate 109 and / or the mounting bracket 112 may be shaped to include one or more bends so that an outer portion of the mounting bracket 112 may be substantially coplanar with an outer portion of the lead frame 106. In some embodiments, the mounting bracket plate 109 may be integral with the mounting bracket 112.

[0045] The compact electronic power assembly 101, the U-clip 105, the wire bonding piece 107, the island 108, the mounting bracket plate 109, a portion of the lead frame 106, and a portion of the mounting bracket 112 may be encapsulated by an encapsulant 110 to complete the compact power module 100. In some embodiments, the encapsulant 110, such as a polymer material, may be an epoxy molding compound (EMC) for sealing and protecting the various components of the compact electronic power assembly 101.

[0046] Figure 2 FIG. 1 is a top plan view of a compact power module 100 according to a first embodiment of the present disclosure, showing its layout, relative sizes, and connections between various components. Due to the efficient layout of the compact electronic power component 101, the DBM structure 102 occupies only about half of the interior space within the encapsulation package defined by the encapsulant 110. In some embodiments, the size of the compact electronic power component 101 is about 13 mm×15 mm, or an area of ​​about 190 mm. 2 About 200mm 2According to simulation results, these dimensions are approximately 40% smaller than current designs for power inverters while providing equivalent thermal performance. Reducing the size of the DBM structure 102 is equivalent to reducing costs by approximately 40%.

[0047] In the illustrated layout, chip assembly 104a and chip assembly 104b are arranged side by side, with each die in a vertical position so that wire bonds can be directly connected. Island 108 is used as a connection pad, such as a gate pad, which rewires horizontal wire bonds 107a and 107b to vertical wire bonds 107c. Therefore, by utilizing island 108, 90-degree bends in the wire bonds can be avoided to improve reliability. Wire bond 107a couples the gate terminal of chip assembly 104a to the gate terminal of chip assembly 104b. Wire bond 107b couples the gate terminal of chip assembly 104b to the first terminal on island 108. Wire bond 107c connects the second terminal on island 108 to lead post 116. Wire bond 107d directly couples the sensing terminal of chip assembly 104b to lead post 114. Wire bonds 107c and 107d extend in the longitudinal direction of compact power module 100. Thus, the wire bond configuration thus described has fewer leads and a shorter wire bond length than current designs for power inverters.

[0048] Figure 3 is a rear plan view of a compact power module 100 according to some embodiments of the present disclosure. Figure 3 The external parts of the compact power module 100 are shown, including the encapsulant 110 and other parts extending from the encapsulant 110 - the mounting bracket 112, the lead frame 106, the lead posts 114 and 116, and the lower DBC layer 102c. The mounting bracket 112 and the lead frame 106 provide mechanical coupling at either end of the compact power module 100, while the lead posts 114 and 116 provide electrical coupling for the compact power module 100.

[0049] Figure 3 The compact DBM structure 102 is also shown to be substantially square with a side length of s. In some embodiments, the three-layer DBM structure 102 is disposed in an opening in the encapsulant 110 such that the lower DBC layer 102c is exposed to the back side of the compact power module 100. Figure 2As shown, the upper DBC layer used as the die attach pad 102a exposes the front side of the compact power module 100. Therefore, the DBM structure 102 can radiate heat from both the back side and the front side of the compact power module 100, acting as a double-sided heat sink to dissipate heat generated by the compact electronic power components 101. The openings in the encapsulant 110 help ensure that the radiated heat is not trapped in the package of the compact power module 100. In some embodiments, enhanced heat transfer through the back side can compensate for the smaller size of the DBM structure 102.

[0050] Figure 4A is a perspective view of a compact power module 400 according to a second embodiment of the present disclosure. The compact power module 400 is similar to the compact power module 100 in that it includes common parts such as a lead frame 106, an encapsulant 110, a mounting bracket 112, and lead posts 114 and 116 arranged in a similar design to the compact power module 100. However, the compact power module 400 is different from the compact power module 100 in that a compact electronic power component 401 replaces the compact electronic power component 101. The compact electronic power component 401 includes two layers of DBC 402 instead of three layers of DBC 102 and an F-shaped clip 405 instead of the U-shaped clip 105. In addition, the shape of the mounting bracket plate 409 that couples the compact electronic power component 401 to the mounting bracket 112 is different from the mounting bracket plate 109.

[0051] In some embodiments, the compact electronic power component 401 occupies a larger area than the compact electronic power component 101, and the area occupied by the compact electronic power component 401 is rectangular. However, the size of the compact electronic power component 401 is still small relative to the size of the entire package. In some embodiments, the compact electronic power component 401 is centered within the encapsulant 110. In some embodiments, since there is less space between the mounting bracket 112 and the compact electronic power component 401 with a larger rectangular area, the mounting bracket plate 409 is narrower and shorter than the mounting bracket plate 109. In some embodiments, the edge of the mounting bracket plate 409 that falls on the upper DBC layer 402a can be a wavy edge or a scalloped edge. In some embodiments, the mounting bracket plate 409 can be integral with the mounting bracket 112.

[0052] In some embodiments, the compact electronic power component 401 provides a different solution for coupling the chip assembly 104 to the lead frame 106 and the lead posts 114 and 116. Specifically, the compact electronic power component 401 includes a DBC 402, an F-clip 405, and wire bonds 407 (three are shown). In the compact electronic power component 401, the chip assembly 104 is rotated 90 degrees clockwise relative to the orientation of the chip assembly 104 in the compact electronic power component 101. Therefore, the compact electronic power component 401 includes an F-clip 405 that is substantially aligned in the same direction as the gate connection to the lead post 116. The F-clip 405 has two tabs 403 that extend in a direction transverse to its body (e.g., aligned with the x-direction) (e.g., aligned with the y-direction). In some embodiments, the F-clip 405 may include a slot 410 that may assist in releasing heat and may reduce the weight of the F-clip 405.

[0053] Figure 4B is a perspective view of a compact power module 450 according to a third embodiment of the present disclosure. Figure 4A The illustrated compact power module 400 has many common features, wherein a compact electronic power component 451 replaces the compact electronic power component 401. The compact electronic power component 451 has substantially the same rectangular footprint and DBC 402 as the compact electronic power component 401. Figure 4A As shown, the compact electronic power assembly is centered within the encapsulant 110 .

[0054] Compact power assembly 451 provides another alternative solution for coupling chip assembly 104 to lead frame 106 and lead posts 114 and 116. Specifically, compact electronic power assembly 451 includes wire bonds 457 (two are shown) and F-clip 455 that are different from corresponding elements of compact electronic power assembly 401. In compact electronic power assembly 451, chip assembly 104 is also rotated 90 degrees clockwise relative to the orientation of chip assembly 104 in compact electronic power assembly 101, and F-clip 455 has two tabs 453 that extend in a direction transverse to its body (e.g., aligned with the x-direction) (e.g., aligned with the y-direction). In some embodiments, F-clip 455 may include a slot 410 that may assist in releasing heat and may reduce the weight of F-clip 455. In addition, F-clip 455 includes an arm 462 that is directly coupled to lead post 114.

[0055] Figure 5A According to the second embodiment of the present disclosure Figure 4AA top plan view of a compact power module 400 is shown. Figure 5A The layout, relative sizes, and connections between various components of the second embodiment of the present disclosure are shown. In some embodiments, the rectangular dimensions L×s of the compact electronic power assembly 401 are approximately 17.5 mm×14.0 mm, or an area of ​​approximately 240 mm 2 To about 250mm 2 According to simulation results, these dimensions are approximately 30% smaller than current designs for power inverters while providing equivalent thermal performance. Reducing the size of the DBM structure 102 is equivalent to reducing costs by approximately 30%.

[0056] Turning to the compact electronic power assembly 401, in some embodiments, the chip assembly 104 is rotated 90 degrees so that the gate terminal and the sense terminal are closer to the lead posts 114 and 116. This rotational orientation allows the wire bonds 407 to run straight without bending around the corners. By utilizing the wire bonds 407 running straight, islands such as island 108 or cutouts along the perimeter of the DBC 402 are also not required. In the example shown, wire bonds 407a and 407b directly couple the gate terminals of the chip assemblies 104a, 104b to the lead post 116. Wire bond 407c directly couples the sense terminal of the chip assembly 104b to the lead post 114.

[0057] The shape and orientation of the F-clip 405 and the three wire bonds 407a, 407b, and 407c can then be adapted to the layout of the compact electronic power assembly 401. In some embodiments, the width of the tab of the F-clip 405, for example, w1, is similar to the width of the two parallel portions of the body on either side of the slot 410. In some embodiments, the width w2 of the body of the F-clip exceeds the tab width w1 by at least two times.

[0058] Figure 5B According to the third embodiment of the present disclosure Figure 4B 4. A top plan view of the compact power module 450 is shown. Turning to the compact electronic power assembly 451, in some embodiments, the chip assembly 104 is rotated 90 degrees so that the gate terminal and the sense terminal are closer to the lead posts 114 and 116. This rotational orientation allows the wire bonds 457 to run straight without bending around the corners. By utilizing the wire bonds 457 running straight, there is also no need for an intermediate gate pad such as the island 108 or a cutout along the perimeter of the DBC 402. By utilizing Figure 5B The arrangement of wire bonds 457 shown improves reliability by about 10% to about 15% over current designs.

[0059] The shape and orientation of the F-clip 455 and the two wire bonds 457a, 457b can then be adapted to the layout of the compact electronic power assembly 451. In the example shown, the wire bonds 457a and 457b directly couple the gate terminals of the chip assemblies 104a, 104b to the lead post 116. The arm 462 of the F-clip 455 couples the sense terminal of the chip assembly 104b to the lead post 114. In some embodiments, the tabs of the F-clip 455 are larger than the lead post 114. Figure 5A The tab of the F-clip 405 is shown to be wider. In some embodiments, the width of the tab of the arm 460 and F-clip 455, such as w1, can be similar to the width of the two parallel portions of the body on either side of the slot 410. In some embodiments, the width w2 of the body of the F-clip exceeds the width of the tab w1 by at least two times.

[0060] Figure 6 According to some embodiments of the present disclosure, Figure 5A and Figure 5B A rear plan view of either the compact power module 400 or the compact power module 450 is shown. Figure 6 and Figure 3 A rear side view of a compact power module 100 is shown for comparison. Figure 6 External parts of the compact power modules 400 and 450 are shown, including the encapsulant 110 and other parts extending from the encapsulant 110 - mounting brackets 112, lead frame 106, and lead posts 114 and 116. The mounting brackets 112 and lead frame 106 provide mechanical coupling at the ends of the compact power modules 400 / 450, while the lead posts 114 and 116 provide electrical coupling for the compact power modules 400 / 450. The encapsulant 110 exposes the DBC 402 through an opening in the encapsulant 110. In some embodiments, two layers of DBC 402 are disposed in the opening in the encapsulant 110 such that the ceramic layer 402b exposes the back side of the compact power module 400 / 450 and the upper DBC layer 402a, which serves as a die attach pad, exposes the front side of the compact power module 400 / 450, as shown. Figure 5A and Figure 5B The DBC structure 402 can thus radiate heat from both the back side and the front side, acting as a double-sided heat sink to dissipate the heat generated by the compact electronic power component 401 . Figure 6 The DBC 402 is shown to be rectangular with a width s and a length L that is longer than the side s of the DBM structure 102 .

[0061] Figure 7 is a flowchart illustrating a method 700 for manufacturing a power module (eg, a compact power module 100) according to some embodiments of the present disclosure. Figure 1, Figure 2 , Figure 3 , Figure 4A , Figure 4B Figure 5 Figure 6 A and Figure 6 Some embodiments described in B perform operations 702 to 210 of method 700 to form a compact power module 100. The operations of method 700 may be performed in a different order, or not performed, depending on the specific application. It should be noted that method 700 may not produce a complete compact power module 100. Therefore, it should be understood that additional processes performed before, during, or after method 700 may be provided, and some of these additional processes may be briefly described herein.

[0062] At 702, according to one embodiment of the present disclosure, method 700 includes attaching a back side of chip assembly 104 to a DBM structure. Attaching the chip assembly may be accomplished using, for example, an adhesive.

[0063] At 704, according to one embodiment of the present disclosure, method 700 includes forming a clip, such as one of the U-shaped clip 105 or the F-shaped clip 405 / 455, attached to the lead frame 106. In some embodiments, the clip and the lead frame 106 may be formed together from a rolled copper sheet.

[0064] At 706, according to one embodiment of the present disclosure, method 700 includes attaching a clip to a top surface of chip assembly 104. In some embodiments, the clip can be soldered to chip assembly 104 using, for example, a silver sintering material.

[0065] At 708, according to one embodiment of the present disclosure, method 700 includes coupling a gate terminal and a sense terminal of chip assembly 104 to lead frame posts 114 and 116. In some embodiments, the gate terminal can be directly coupled to lead frame post 116 via a wire bond. In some embodiments, two wire bonds coupled in series can be used to route a connection around a corner. In some embodiments, an arm of a clip can be coupled between the sense terminal and lead frame post 114.

[0066] At 710, according to one embodiment of the present disclosure, method 700 includes an encapsulation operation. In some embodiments, the encapsulation operation encompasses internal parts including compact electronic power assembly 101, wire bonds 107, island 108, mounting bracket plate 109, portions of lead frame 106, portions of mounting bracket 112, and horizontal portions of lead frame columns 114 and 116. The internal parts are surrounded by an encapsulant such as epoxy molding compound to complete the manufacture of compact power module 100. Encapsulation can be accomplished by, for example, an injection molding process or a transfer molding process.

[0067] As described above, various embodiments of compact power modules can reduce the DBC by about 30% to about 40% while maintaining approximately the same heat dissipation. By further changing the layout of components mounted on a smaller DBM structure, the number of wire bonds can be reduced and the wire bonds can be routed to avoid corners. Such changes can improve the reliability of wire bonds by about 10% to about 15%.

[0068] It should be understood that in the foregoing description, when an element such as a layer, a region or a substrate is mentioned on another element, connected to another element, electrically connected to another element, coupled to another element or electrically coupled to another element, the element may be directly on another element, connected or coupled to another element or one or more intermediate elements may exist. On the contrary, when an element is mentioned directly on another element or layer, directly connected to another element or layer or directly coupled to another element or layer, there is no intermediate element or layer. Although the term directly on..., directly connected to..., or directly coupled to... may not be used in the entire specific embodiment, the element shown as being directly located on the element, directly connected or directly coupled can be mentioned in this manner. The claims of the present application may be revised to narrate the exemplary relationship described in the specification or shown in the drawings.

[0069] As used in this specification, unless the context clearly indicates a particular case, the singular form may include the plural form. In addition to the orientation shown in the drawings, spatial relative terms (e.g., above, above, above, below, below, below, below, at the top, at the bottom, etc.) are intended to cover different orientations of the device in use or operation. In some embodiments, the relative terms above and below may include vertically above and vertically below, respectively. In some embodiments, the term adjacent may include lateral adjacent or horizontal adjacent.

[0070] Some embodiments may be implemented using various semiconductor processing and / or packaging technologies. Some embodiments may be implemented using various types of semiconductor device processing technologies associated with semiconductor substrates, including but not limited to, for example, silicon (Si), silicon carbide (SiC), gallium arsenide (GaAs), gallium nitride (GaN), etc.

[0071] Although certain features of the described embodiments have been described as described herein, those skilled in the art will now recognize many modifications, alternatives, variations, and equivalents. For example, features illustrated with respect to one embodiment may also be included in other embodiments where appropriate. Therefore, it should be understood that the appended claims are intended to cover all such modifications and variations that fall within the scope of the embodiments. It should be understood that these modifications and variations are presented only by way of example and not limitation, and that various changes in form and detail may be made. In addition to mutually exclusive combinations, any part of the apparatus and / or method described herein may be combined in any combination. The embodiments described herein may include various combinations and / or sub-combinations of the functions, components, and / or features of the different embodiments described.

Claims

1. A device (400, 450), comprising: A lead frame (106) having a gate lead frame post (116), a sense lead frame post (114), and a ground connection (106); A direct bond metal (DBM) structure (102), the DBM structure comprising an insulating layer (102b); a first die (104a) and a second die (104b), the first die and the second die being attached to the DBM structure (102) in parallel; a metal clip (405, 455) having a first tab for coupling a top side of the first die (104a) to the lead frame (106) using solder and having a second tab for coupling a top side of the second die (104b) to the lead frame using solder; and An electrical connector (407a, 457a) directly couples a gate terminal of the first die (104a) to the gate leadframe post (116).

2. The apparatus of claim 1, further comprising wire bonds (407c) coupling a sense terminal of the second die (104b) to the sense leadframe post (114).

3. The apparatus of claim 1, further comprising an arm (460) of the metal clip (455), the arm coupling a sense terminal of the second die (104b) to the sense lead frame post (114).

4. The apparatus of claim 1, wherein the metal clip (405, 455) is connected to the ground connection (106).

5. A device (100), comprising: A lead frame portion (106); A direct bond metal (DBM) structure (102) includes a first metal layer (102a), a second metal layer (102c), and a ceramic layer (102b) disposed between the first metal layer (102a) and the second metal layer (102c). a first die (104a) and a second die (104b), the first die and the second die being attached in parallel to the die attach pad (102a) of the DBM structure (102); a U-shaped metal clip (105) having a first tab coupled to a top side of the first die (104a) and having a second tab coupled to a top side of the second die (104b), the U-shaped metal clip (105) being coupled to the lead frame portion (106); and A wire bonding part (107), the wire bonding part comprising: a first wire bond (107a) coupling a gate terminal of the first die (104a) to a gate terminal of the second die (104b), and A second wire bond (107b) couples the second die (104b) to a gate pad (108).

6. The apparatus of claim 5, further comprising a third wire bond (107d) coupling a sense terminal of the second die (104b) to a sense lead frame post (114).

7. The apparatus of claim 5, wherein the wire bonds (107) further include a fourth wire bond (107c) coupling the gate pad (108) to a gate lead frame post (116).

8. The apparatus of claim 7, wherein the first wire bond (107a) extends in a lateral direction relative to the gate leadframe post (116).

9. The device of claim 5, wherein the length dimension and the width dimension of the DBM structure (102) are each less than 15 mm.

10. The device of claim 5, wherein the wire bonds (107) are made of 300 μm aluminum wire.

11. The apparatus of claim 5, wherein the first die (104a) and the second die (104b) comprise silicon carbide (SiC).

12. A method (700), comprising: coupling (702) the backsides of the first die (104a) and the second die (104b) to a direct bond metal (DBM) structure (102); forming (704) a lead frame (106) and a metal clip (105, 405, 455); coupling (706) the metal clip (105, 405, 455) between the top sides of the first die (104a) and the second die (104b) and a ground plane of the lead frame (106); coupling (708) a gate terminal of the first die (104a) and a gate terminal of the second die (104b) to a first lead frame post (116); as well as A sense terminal of the second die (104b) is coupled (708) to a second lead frame post (114).

13. The method of claim 12, wherein coupling the gate terminal of the first die (104a) and the gate terminal of the second die (104b) to the first leadframe column (116) comprises using wire bonds (107).

14. The method of claim 13, wherein coupling the gate terminal to the first lead frame column (116) comprises directly coupling the gate terminal of the first die (104a) to the gate terminal of the second die (104b) and coupling the gate terminal of the second die (104b) to the first lead frame column (116).

15. The method of claim 14, wherein coupling the gate terminal of the second die (104b) to the first lead frame column (116) comprises coupling the gate terminal of the second die (104b) to a gate pad (108) and coupling the gate pad (108) to the first lead frame column (116).

16. The method of claim 12, wherein coupling the sense terminal to the second lead frame post (114) comprises using a wire bond (107d, 407c).

17. The method of claim 12, wherein coupling the sense terminal to the second lead frame post (114) comprises using an arm (460) of the metal clip (455).

18. The method of claim 12, wherein forming the metal clip (105, 405, 455) comprises forming the metal clip (105, 405, 455) from copper.

19. The method of claim 12, wherein forming the lead frame (106) comprises forming the lead frame (106) from copper.

20. The method of claim 12, further comprising encapsulating (710) the DBM structure (102) in a package (110), wherein a back side of the package (110) exposes a lower layer (102c) of the DBM structure (102).

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