Power stage device with support frame for a power stage module and an integrated inductor

Abstract

Having a power device: comprising a frame (106) comprising an electrically insulating material (112), an opening (104) in the electrically insulating material (112), and an electrical conductor (114) extending through the electrically insulating material (112); a power stage module (100) which is attached in the opening (104) in the electrically insulating material (112) and has an output terminal (116) on a first side of the power stage module (100), and a power terminal (118), a ground terminal (120) and a plurality of input / output, ‘I / O’, ​​terminals (122) on a second side of the power stage module (100), which is opposite the first side; and a passive component (102) having a first connection which is connected to the output connection (116) of the power stage module (100) and a second connection which is connected to the electrical conductor (114) of the frame (106), where the passive component (102) has a larger footprint than the power stage module (100), wherein the frame (106) increases the base area of ​​the power stage module (100) in order to accommodate the attachment of the passive component (102) to the power device, where the frame (106) has a lower connection density than the power stage module (100).

Description

[0001] In high-current converters, such as point-of-use (POU) converters, point-of-load (POL) converters, and other types of AC-to-DC and DC-to-DC converters, the output inductor is typically significantly larger than the converter's actual power stage module, which contains the power stage of the converter. For example, the inductor footprint can be 1.5 times, 2 times, or even larger than the power stage module. The size of the power stage module is typically increased to accommodate the integrated inductor. However, the module substrate used to embed the components of a POL or power stage provides most of the electrical connections for the power stage module and typically contains multiple layers, has small pitches, etc., and is therefore expensive.Increasing the size of the module substrate simply to accommodate a large inductor significantly increases the overall cost of the device, without offering any advantages other than integrating the inductor and the power stage module into the same device. DE 11 2016 007 304 T5 discloses a structure 100 configured as an interposer housing with an embedded die. The structure 100 comprises a die 102 and a housing substrate 130. The housing substrate 130 includes electrical paths 108 for electrically connecting the die 102, which is connected to the electrical paths 108 via contact surfaces 116. A molding compound 110 surrounds the die 102 and the contact surfaces 116.

[0002] DE 11 2014 003 166 T5 discloses a stacked semiconductor device assembly 100, comprising a first semiconductor device 104 with a die 104d, a substrate 102 arranged below it, and a second semiconductor device 106 with a die 106d arranged below the substrate 102. The first semiconductor device 104 is surrounded by a molded compound 104e. The second semiconductor device 106 is embedded in a dielectric layer 108. Both dies 104d and 106d are electrically connected to the substrate 102 via interconnect structures 104h and 106h. Conductivity features 108c are arranged as electrical paths in the substrate 102 and the dielectric layer 108.

[0003] There is a need for a more cost-effective solution for integrating an inductor with the power stage module of a power converter. Summary

[0004] According to one embodiment of a power device, the power device comprises: a frame having an electrically insulating material, an opening in the electrically insulating material, and an electrical conductor extending through the electrically insulating material; a power stage module which is fixed in the opening in the electrically insulating material and has an output terminal on a first side of the power stage module, and a power terminal, a ground terminal, and a plurality of input / output (I / O) terminals on a second side of the power stage module which is opposite the first side;and a passive component comprising a first connection which is connected to the output connection of the power stage module and a second connection which is connected to the electrical conductor of the frame, wherein the passive component has a larger footprint than the power stage module, wherein the frame increases the footprint of the power stage module to accommodate mounting the passive component to the power device, wherein the frame has a lower connection density than the power stage module.

[0005] The only electrical connection provided by means of the frame can be a vertical electrical connection for the second connection of the passive component from an upper surface of the frame to a lower surface of the frame.

[0006] Separately or in combination, the frame can be a first printed circuit board (PCB), the electrical conductor of the frame can have one or more coated through-holes extending from a top surface of the first PCB to a bottom surface of the first PCB, and the first PCB can be free of metal traces extending in a direction perpendicular to the top and bottom surfaces of the first PCB.

[0007] Separately or in combination, the power stage module can have a second PCB and at least one semiconductor wafer embedded in the second PCB between an upper and a lower surface of the second PCB, wherein the second PCB can have at least two layers with microvia connections and metal traces which provide an electrical connection to the at least one semiconductor wafer embedded in the second PCB, and at least some of the metal traces of the second PCB can extend in a direction perpendicular to the upper and lower surfaces of the second PCB.

[0008] Separately or in combination, the second PCB can have a line / space (L / S) ratio of 75 µm / 75 µm or less, and the first PCB can have an L / S ratio of 150 µm / 150 µm or greater.

[0009] The second PCB can be attached to the opening in the first PCB, either separately or in combination, using an adhesive, a mechanical fastening, or a soldering compound.

[0010] Separately or in combination, the frame can be a molded leadframe having a plurality of leads embedded in a molding compound, and the electrical conductor of the frame can have one or more leads from the plurality of leads which are not covered by the molding compound on either an upper surface or a lower surface of the molded leadframe.

[0011] The power stage module may be embedded separately or in combination in the molding compound of the encapsulated conductor frame; the output terminal on the first side of the power stage module may not be covered by the molding compound, and the power terminal, ground terminal, and the majority of I / O terminals on the second side of the power stage module may not be covered by the molding compound.

[0012] Separately or in combination, the electrically insulating material of the frame can be the molding compound, the electrical conductor of the frame can be a metal block embedded in the molding compound, and the metal block may not be covered by the molding compound on either an upper surface of the frame or a lower surface of the frame.

[0013] The power stage module can be embedded in the molding compound separately or in combination; the output terminal on the first side of the power stage module may not be covered by the molding compound, and the power terminal, ground terminal, and the majority of I / O terminals on the second side of the power stage module may not be covered by the molding compound.

[0014] The metal block can be a copper block, either separately or in combination, which contains copper or a copper alloy.

[0015] Separately or in combination, the power stage module can comprise a first power transistor plate, a second power transistor plate, and a driver plate, which are embedded in a PCB and configured as a half-bridge, which has a switched node output that is electrically connected to the output terminal of the power stage module, and the passive component can be an inductor that electrically connects the switched node output to the electrical conductor of the frame.

[0016] According to one embodiment of a power system, the power system comprises: a PCB; and a power device attached to the PCB. The power device comprises: a frame having an electrically insulating material, an opening in the electrically insulating material, and an electrical conductor extending through the electrically insulating material and connected to one or more metal pads on a first side of the PCB; a power stage module attached in the opening in the electrically insulating material, having an output terminal on a side of the power stage module facing away from the PCB, and a power terminal, a ground terminal, and a plurality of input / output (I / O) terminals on a side of the power stage module facing the PCB, each connected to additional metal pads on the first side of the PCB.and a passive component attached to the power device on one side of the power device facing away from the PCB, the passive component having a first terminal connected to the output terminal of the power stage module and a second terminal connected to the electrical conductor of the frame, such that the output terminal of the power stage module is electrically connected to the one or more metal pads on the first side of the PCB by means of the passive component and the electrical conductor of the frame, the passive component having a larger footprint than the power stage module, the frame increasing the footprint of the power stage module to accommodate the mounting of the passive component to the power device, the frame having a lower connection density than the power stage module.

[0017] According to one embodiment of a method for manufacturing a power device, the method comprises: forming a frame having an electrically insulating material, an opening in the electrically insulating material, and an electrical conductor extending through the electrically insulating material; attaching a power stage module in the opening in the electrically insulating material, wherein the power stage module has an output terminal on a first side of the power stage module, and a power terminal, a ground terminal, and a plurality of input / output (I / O) terminals on the second side of the power stage module, which is opposite the first side;and connecting a first terminal of a passive component to the output terminal of the power stage module and a second terminal of the passive component to the electrical conductor of the frame, wherein the passive component has a larger footprint than the power stage module, wherein the frame increases the footprint of the power stage module to accommodate mounting the passive component to the power device, and wherein the frame has a lower connection density than the power stage module.

[0018] The frame formation may, separately or in combination, comprise: forming a first printed circuit board (PCB) having one or more coated through-holes extending from a top surface of the first PCB to a bottom surface of the first PCB, wherein the one or more coated through-holes form the electrical conductor of the frame, wherein the first PCB is free of metal traces extending in a direction perpendicular to the top and bottom surfaces of the first PCB.

[0019] Securing the power stage module in the opening in the electrically insulating material, separately or in combination, may include: mounting the first PCB onto a carrier; mounting the power stage module onto the carrier through the opening in the first PCB; gluing, mechanically fastening, or soldering the power stage module to the first PCB while the power stage module and the first PCB are mounted on the carrier; and after gluing, mechanically fastening, or soldering the power stage module to the first PCB, removing the carrier from the power device.

[0020] Separately or in combination, forming the frame and securing the power stage module in the opening in the electrically insulating material can comprise: mounting a conductor frame on a support, wherein the conductor frame has one or more leads forming the electrical conductor of the frame; mounting the power stage module on the support, laterally spaced from the one or more leads of the conductor frame; embedding the one or more leads of the conductor frame and the power stage module in a molding compound to form an encapsulated package, wherein the one or more leads of the conductor frame and the terminals of the power stage module are not covered by the molding compound on either a top surface or a bottom surface of the encapsulated package; and after forming the encapsulated package, removing the support from the encapsulated package.

[0021] Separately or in combination, forming the frame and securing the power stage module in the opening in the electrically insulating material can comprise: mounting a metal block onto a support, the metal block forming the electrical conductor of the frame; mounting the power stage module onto the support, spaced laterally from the metal block; embedding the metal block and the power stage module in a molding compound to form a cast package, wherein the metal block and the terminals of the power stage module are not covered by the molding compound on either a top or bottom surface of the cast package; and after forming the cast package, removing the support from the cast package.

[0022] Separately or in combination, the metal block may be a copper block containing copper or a copper alloy.

[0023] Separately or in combination, the mounting of the power stage module in the opening in the electrically insulating material can comprise: embedding a first power transistor chip, a second power transistor chip, and a driver chip, which are embedded in a PCB and configured as a half-bridge having a switched node output electrically connected to the output terminal of the power stage module; and mounting the PCB in the opening in the electrically insulating material, wherein the passive component is an inductor electrically connecting the switched node output to the electrical conductor of the frame.

[0024] Upon reading the following detailed description and examining the accompanying drawings, the expert will become aware of additional features and advantages. Brief description of the characters

[0025] The elements in the drawings are not necessarily to scale with respect to one another. Identical reference numerals denote corresponding similar parts. The features of the various embodiments shown can be combined, provided they are not mutually exclusive. Embodiments are illustrated in the drawings and are described in more detail below. Fig. Figure 1A shows a cross-sectional view of an embodiment of a power device which includes a power stage module of a power converter which is integrated with a passive component of the converter. Fig. Figure 1B shows a top view of the upper side of a frame of the power device to which the passive component is mounted. Fig. Figure 1C shows a top view of the underside of the frame. Fig. Figures 2A to 2D show partial under-views of different embodiments for attaching the power stage module in an opening of the frame. Fig. Figures 3A to 3E, 4A to 4E, 5A and 5B show an embodiment of a method for manufacturing the power device. Fig. Figures 3A to 3E show cross-sectional views during different stages of the manufacturing process. Fig. 4A to 4E show corresponding top views, and Fig. 5A and Fig. Figures 5B show cross-sectional views after the passive component has been attached to the power device. Fig. Figures 6A to 6H each show cross-sectional views of a different embodiment of a method for manufacturing the power device during different stages of the manufacturing process. Fig. Figures 7A to 7G each show cross-sectional views of a further embodiment of a method for manufacturing the power device during various stages of the manufacturing process. Fig. Figure 8 shows an exemplary schematic diagram of a half-back type power level, which can be implemented using the power level module of the power device. Detailed description

[0026] The embodiments described here provide a power device containing a power stage module of a power converter, which is integrated with one or more passive components of the converter. The power stage module is mounted in an opening of an electrically insulating frame. The frame increases the footprint of each power stage module to accommodate the mounting of a corresponding passive component of the converter to the power device. The frame has a lower interconnect density than each power stage module it holds. This allows for the use of a less expensive electrically insulating material, such as a lower-density printed circuit board (PCB), molding compound, etc., for the frame, while a denser (and more expensive) PCB can be used for each power stage module.The resulting power device thus has lower overall costs, while still integrating one or more passive components of the power converter with the power stage module(s).

[0027] Fig. Figure 1A shows a cross-sectional view of an embodiment of a power device which includes a power stage module 100 of a power converter which is integrated with a passive component 102 of the converter, wherein the power stage module 100 is fixed in an opening 104 of an electrically insulating frame 106. Fig. Figure 1B shows a top view of the top 108 of the frame 106, i.e. the side of the frame 106 on which the passive component 102 is mounted. Fig. Figure 1C shows a top view of the underside 110 of the frame 106, i.e., the side of the frame 106 facing away from the passive component 102. The cross-section in Fig. 1A is along line AA' in the Fig. 1B and Fig. Taken from 1C.

[0028] The type of power device depends on the type of power converter. For example, the power converter may be a switched-capacitor converter, and the passive component 102 may contain one or more capacitors of the switched-capacitor converter. In another example, the power converter may be an isolated converter or a non-isolated converter, and the passive component 102 may be an output inductor. The converter may be resonant or non-resonant. The power converter may contain one power stage module 100 in the case of a single-phase converter, or more than one power stage module 100 in the case of a multi-phase converter (for example, one power stage module per phase), with each phase configured to contribute to the total load current.Further combinations of power converter and passive component types can be integrated in accordance with the power device design forms described here.

[0029] In general, the frame 106 of the power device includes an electrically insulating material 112, an opening 104 in the electrically insulating material 112, and an electrical conductor 114 extending through the electrically insulating material 112. A power stage module 100 is mounted in the opening 104 in the electrically insulating material 112 of the frame 106. The power stage module 100 includes an output terminal 116 on the top of the power stage module 100 ( Fig. 1C), and a power terminal 118, a ground terminal 120 and a plurality of input / output (I / O) terminals 122 on the underside of the power stage module 100 (see Fig. 1B). The passive component 102 is mounted on the top of the power stage module 100. The passive component 102 can be a capacitor or an inductor, depending on the type of power device and power converter.

[0030] The passive component 102 has a first terminal 124, which is connected to the output terminal 116 of the power stage module 100, and a second terminal 126, which is connected to the electrical conductor 114 of the frame 106. The terminals 124 and 126 of the passive component 102 can be connected directly or using a suitable material 128, such as solder, adhesive, etc. The electrical conductor 114 of the frame 106 provides an electrical connection between the upper and lower sides 108 and 110 of the frame 106 for the second terminal 126 of the passive component 102. The passive component 102 has a larger footprint than the power stage module 100. The frame 106 increases the footprint of the power stage module 100 to accommodate the mounting of the passive component 102 to the power device.Frame 106 has a lower connection density than power stage module 100 and is therefore less expensive. In this way, the footprint of power stage module 100 is effectively increased in a cost-effective manner, for example, compared to manufacturing the more expensive power stage module larger simply to accommodate the passive component 102. The passive component 102 is not included in the... Fig. 1B and Fig. 1C shown, so that the features of the power stage module 100 and the frame 106 can be seen without restriction in these figures.

[0031] Any electrically insulating material 112 with a lower density can be used for the frame 106, since the primary electrical connection provided for the second terminal 126 of the passive component 102 by means of the frame 106 is located between the upper and lower sides 108, 110 of the frame 106. In one embodiment, the only electrical connection provided by means of the frame 106 is the electrical conductor 114 of the frame 106, which provides an electrical connection between the upper and lower sides 108, 110 of the frame 106 for the second terminal 126 of the passive component 102. Thus, a higher-density electrically insulating material with many layers and microvia connections is not necessary for the frame 106.In one embodiment, the electrically insulating material 112 of the frame 106 is an insulating substrate of a lower-density PCB, for example, FR-4 glass epoxy, a modified epoxy, polyimide, etc. In another embodiment, the electrically insulating material 112 of the frame 106 is a molding compound. Molding compounds are generally composite materials containing, for example, epoxy resin, phenolic hardeners, silicon dioxide (silica), catalysts, pigments, mold release agents, etc. Furthermore, other types of lower-density electrically insulating materials 112 can be used for the frame 106.

[0032] In the case of a lower-density PCB as frame 106, the electrical conductor 114, which provides an electrical connection between the upper and lower sides 108, 110 of the frame 106 for the second terminal 126 of the passive component 102, can be a single (large) coated through-hole or a plurality of (smaller) coated through-holes. In the case of a molding compound as frame 106, the electrical conductor 114 can be a metal (e.g., Cu) block or one or more leads of a conductor frame. Other types of electrical conductors 114 can be used, depending on the type of electrically insulating lower-density material 112 used for the frame 106.

[0033] In one embodiment, the power stage module 100, which is mounted in the opening 104 of the frame 106, contains a higher-density PCB (higher-density PCB) with multiple layers, small pitches, etc., in which the semiconductor component(s) of the power stage module are embedded. The power stage forms a phase of the power converter, which can be single-phase or multi-phase, as described above. Semiconductor components of the power stage can include one or more power transistors, such as, but not limited to, power MOSFETs (metal-oxide semiconductor field-effect transistors), IGBTs (insulated-gate bipolar transistors), HEMTs (high-electron-mobility transistors), etc.

[0034] The power stage module 100 can contain a single power transistor, such as a synchronous rectifier switch, or multiple power transistors, such as in the case of a half-bridge or full-bridge rectifier. Other semiconductor components of the power stage module 100 can include a driver for driving the gates of the power transistor(s), a controller for controlling the operation of the power stage, etc. The controller and / or driver can be integrated into the power stage module 100 or provided in a separate module. As outlined above, the number and type of devices that constitute the power stage depend on the type of converter. The semiconductor components contained in the power stage module 100 can be integrated onto the same semiconductor chip or provided on separate chips.

[0035] In general, each semiconductor wafer 130 contained in the power stage module 100 is embedded in a higher-density PCB or a similar chip-embedding structure 132. The term "higher density" here means that the chip-embedding structure 132 of the power stage module 100 is sufficiently compact to provide the necessary electrical connections for each semiconductor wafer 130 embedded in the chip-embedding structure 132 in the smallest possible or technically feasible area, so that the power stage module 100 does not have an excessively or unnecessarily large footprint. For example, the chip-embedding structure 132 can be a high-density interconnection (HDI) PCB, which is a PCB that has a higher wiring density per unit (e.g., a line / space of typically 35–150 µm), where the vertical connections in the PCB are typically coated, laser-drilled microvias (e.g.,The through-connections between the layers can be implemented with stacked microvias or small coated through-holes of 75-150 µm, where the capture lands for the vias and the coated through-holes are much smaller than in conventional PCBs. The PCB material is typically an FR4 or BT resin material with a medium or high Tg (glass transition temperature) or an FR4 material with a low CTE (coefficient of thermal expansion). The PCB material is significantly purer than conventional PCB material (e.g., very low halogen content – ​​more expensive and purer raw materials are required). In the case of an HDI PCB as a chip-embedding structure 132, more expensive materials and more costly PCB manufacturing processes are used to fabricate the chip-embedding structure 132.

[0036] For example, in the case of a higher-density PCB than the chip-embedding structure 132 of the power stage module 100, the chip-embedding structure 132 can have two, three, four, or more layers of electrically insulating materials in which each semiconductor wafer 132 of the power stage is embedded, with microvia connections between each semiconductor wafer 130 and the chip-embedding structure 132, and coated through-holes of small size between the top and bottom of the chip-embedding structure 132. For example, the size of the microvia connections can be between 50 and 150 µm, the size of the coated through-holes can be between 100 µm and 200 µm, and copper can fill the coated through-holes and microvias. The pattern dimensions (L / S) of the chip-embedding structure 132 can be 75 µm / 75 µm or smaller in the case of a higher density PCB.Such a higher-density PCB or similar chip-embedding structure can be constructed from FR-4 (or similar) material, from a high-purity material (e.g., with a chlorine content typically less than 20 ppm), and can be very expensive (e.g., typically 20–50 times or even 100 times more expensive than conventional low-cost bilayer PCBs). Even other types of chip-embedding structures 132 can be used for the power stage module 100. In general, the chip-embedding structure 132 of the power stage module 100 has a higher interconnect density than the frame 106.

[0037] Regardless of the type of chip-embedding structure 132 used for the power stage module 100 and the number of semiconductor wafers 132 embedded in the chip-embedding structure 132, the power stage module 100 is mounted in the opening 104 in the electrically insulating material 112 of the frame 106. The output terminal 116 on the upper side of the power stage module 100 is connected to the first terminal 124 of the passive component 102. The power terminal, the ground terminal, and the I / O terminals 118, 120, 122 on the lower side of the power stage module 100 are accessible for connection to another structure 134, for example, another power stage module, a printed circuit board, etc., to form a power system, such as a POU converter, a POL converter, or any other type of AC-to-DC or DC-to-DC converter.The electrical conductor 114, which extends through the electrically insulating material 112 of the frame 106, provides a point for the electrical connection of the second terminal 126 of the passive component 102 on the same side of the power device as the power terminal, the ground terminal and the I / O terminals 118, 120, 122 of the power stage module 100.

[0038] Fig. Figures 2A to 2D show bottom views of respective embodiments for attaching the power stage module 100 in the opening 104 of the frame 106. Fig. 2A to 2D shows only a part of frame 106.

[0039] In Fig. 2A The power stage module 100 is attached to the opening 104 in the electrically insulating material 112 of the frame 106 by means of an adhesive 200. The power stage module 100 is in Fig. 2A is shown attached to the frame 106 along all four sides of the opening 104. In general, the power stage module 100 can be attached to the frame 106 along one, two, three or all four sides of the opening 104. In Fig. 2B, the power stage module 100 is mechanically fastened in the opening 104 in the electrically insulating material 112 of the frame 106. For example, the opening 104 in the electrically insulating material 112 of the frame 106 can have one or more surface features 202 which mate with a corresponding surface feature 204 on the edge surface of the power module 100 to mechanically fasten the power module 100. In the Fig. 2C and Fig. In 2D, the power stage module 100 is attached to the electrically insulating material 112 of the frame 106 in the opening 104 by means of a soldering agent. According to these embodiments, the frame 106 includes at least one metal structure 206, which is laterally aligned with a corresponding metal structure 208 of the power stage module 100 in order to form at least one solderable connection between the frame 106 and the power stage module 100. Fig. 2C, the frame 106 contains a plurality of metal structures 206, each of which is laterally aligned with a corresponding metal structure 208 of the power stage module 100, separate from the terminals 118, 120, 122 on the lower side of the module 100, in order to form the solderable connections. Fig. 2D some of the connections 118 on the lower side of the power stage module 100 form part of the solderable connections.

[0040] The following describes various embodiments of methods for manufacturing the power device described here.

[0041] Fig. Figures 3A to 5B show an embodiment of a method for manufacturing the power device described here. Fig. Figures 3A to 3E show cross-sectional views during different stages of the manufacturing process. Fig. 4A to 4E show corresponding top views, and Fig. 5A and Fig. Figures 5B show cross-sectional views after the passive component 102 has been attached to the power device.

[0042] Fig. 3A and Fig. 4A shows the power stage module 100 and Fig. 3B and Fig. Figure 4B shows the frame 106 before the power stage module 100 is attached to the opening 104 of the frame 106. The frame 106 contains an electrically insulating material 112, an opening 104 in the electrically insulating material 112, and an electrical conductor 114 extending through the electrically insulating material 112, as previously described. The power stage module 100 has an output terminal 116 on its upper side, and a power terminal, a ground terminal, and I / O terminals 118, 120, 122 on its lower side, also as previously described. The frame 106 increases the footprint of the power stage module 100 to accommodate the mounting of a passive component 102 to the power device, and the frame 106 has a lower connection density than the power stage module 100.

[0043] According to the embodiment which is in the Fig. As shown in Figures 3A to 4E, frame 106 is implemented as a lower-density PCB. The electrical conductor 112 of frame 106 is one or more coated vias extending from an upper surface of the lower-density PCB to a lower surface of the lower-density PCB. The lower-density PCB is free of metal traces extending in a direction perpendicular to both the upper and lower surfaces of the lower-density PCB. For example, the size of the coated vias can be in the range of 200 to 500 µm or larger, or, if copper-filled vias are used, in the range of 150 to 200 µm.Furthermore, according to this embodiment, the power stage module 100 is implemented as a high-density PCB with at least one semiconductor wafer 130 embedded in the high-density PCB between an upper and a lower surface of the PCB. The high-density PCB has at least two layers with microvia connections and metal traces that provide electrical connections to the at least one semiconductor wafer 130 embedded in the PCB. At least some of the metal traces of the high-density PCB extend in a direction perpendicular to the upper and lower surfaces of the PCB.

[0044] Fig. 3C and Fig. Figure 4C shows the lower-density PCB of frame 106, which is mounted on a carrier 300, for example, a carrier tape. The opening 104 in the frame 106 extends completely through the lower-density PCB, so that part of the carrier 300 remains exposed through the opening 104.

[0045] Fig. 3D and Fig. Figure 4D shows the power stage module 100, which is mounted on the exposed part of the support 300 through the opening 104 in the frame 106.

[0046] Fig. 3E and Fig. Figure 4E shows the power stage module 100, which is attached to the frame 106, while the power stage module 100 and the frame 106 are mounted on the carrier 300, for example by gluing, mechanical fastening or soldering the power stage module 100 to the frame 106, as previously described in conjunction with the Fig. 2A to 2D described. The carrier 300 can be removed from the power device after the power stage module 100 has been attached to the frame 106.

[0047] Fig. Figure 5A shows the power device after the support 300 has been removed, and after the first terminal 124 of the passive component 102 has been connected to the output terminal 116 of the power stage module 100, and the second terminal 126 of the passive component 102 has been connected to the electrical conductor 114 of the frame 106. The passive component 102 has a larger footprint than the power stage module 100, and the frame 106 increases the footprint of the power stage module 100 to accommodate the mounting of the passive component 102 to the power device.

[0048] Fig. Figure 5B shows the power unit during a singulation process, which separates the power unit from other power units being manufactured simultaneously. Any typical singulation process, such as sawing, can be used to singulate the individual power units. The singulation process is represented by dashed boxes in Figure 5B. Fig. 5B is shown.

[0049] Fig. Figures 6A to 6H each show cross-sectional views of a different embodiment of a method for manufacturing the power device described here during different stages of the manufacturing process.

[0050] Fig. Figure 6A shows the power stage module 100. According to the embodiment shown in the Fig. As shown in Figures 6A to 6H, the power stage module 100 is implemented as a higher-density PCB with at least one semiconductor wafer 130 embedded in the higher-density PCB between its upper and lower surfaces. The higher-density PCB has at least two layers with microvia connections and metal traces that provide electrical connections to the at least one semiconductor wafer 130 embedded in the higher-density PCB. At least some of the metal traces of the higher-density PCB run in a direction perpendicular to the upper and lower surfaces of the higher-density PCB.

[0051] Fig. Figure 6B shows a conductor frame 400 mounted on a carrier 402, for example, a carrier strip. The conductor frame 400 has one or more leads 404, which form the electrical conductor 114 of the frame 106. In this embodiment, the conductor frame 400 does not have a chip carrier (the paddle).

[0052] Fig. Figure 6C shows the power stage module 100, which is mounted on the carrier 402 and is spaced laterally from the lead(s) of the ladder frame 400.

[0053] Fig. Figure 6D shows the lead(s) 404 of the conductor frame 400 and the power stage module 100, which are embedded in a molding compound 408 to form an encapsulated package. Any molding process typically used to form encapsulated semiconductor packages can be used, such as injection molding, film-assisted molding, transfer molding, etc. The lead(s) 404 of the conductor frame 400 and the terminals 116, 118, 120, 122 of the power stage module 100 are not covered by the molding compound 406 on either the top or bottom surface of the encapsulated package.

[0054] Fig. Figure 6E shows the encapsulated package after removal of carrier 402.

[0055] Fig. Figure 6F shows the encapsulated package after the first terminal 124 of the passive component 102 has been connected to the output terminal 116 of the power stage module 100, and the second terminal 124 of the passive component 102 has been connected to a lead 404 of the conductor frame 400, which forms the electrical conductor 114 of the frame 106. The passive component 102 has a larger footprint than the power stage module 100. The frame 106, which in this embodiment contains the molding compound 406 and the conductor frame 400, increases the footprint of the power stage module 100 to accommodate the mounting of the passive component 102 to the power device.

[0056] Fig. Figure 6G shows the encapsulated package during a singulation process, which separates it from other encapsulated packages being produced simultaneously. Any typical singulation operation, such as sawing, can be used to separate the individual encapsulated packages. The singulation process is represented by dashed boxes in Figure 6G. Fig. 6G is shown.

[0057] Fig. Figure 6H shows one of the individual encapsulated packages. According to this embodiment, the frame 106 of the power device is an encapsulated conductor frame comprising one or more leads 404 embedded in a molding compound 406, and the electrical conductor 114 of the frame 106 is one or more of the leads 404 that are not covered by the molding compound 406 on either the upper or lower surface of the encapsulated conductor frame. Furthermore, according to this embodiment, the power stage module 100 is embedded in the molding compound 406 of the encapsulated conductor frame such that the output terminal 116 on the upper side of the power stage module 100 is not covered by the molding compound 406, and the power terminal, ground terminal, and I / O terminals 118, 120, 122 on the lower side of the power stage module 100 are also not covered by the molding compound 406.According to this embodiment, the power stage module 100 is attached using the molding compound 406. The power stage module 100 and / or the molding compound 406 may have surface features, such as bumps, protrusions, dimples, etc., which facilitate attachment.

[0058] The molding compound-based frame 106 in Fig. 6H is more cost-effective than the lower-density PCB-based frame 106 in Fig. 5B. In addition, the use of the conductor frame(s) as the electrical conductor 112 of the frame 106 provides lower resistance and better heat dissipation than the coated through-holes of the lower-density PCB-based frame 106, which is in Fig. 5B is shown. Furthermore, the conductor frame strips are compatible with typical package assembly processes, such as molding, plating, surface mounting of passive components, and singulation.

[0059] Fig. Figures 7A to 7G each show cross-sectional views of a different embodiment of a method for manufacturing the power device described here during different stages of the manufacturing process.

[0060] Fig. Figure 7A shows the power stage module 100 and a separate metal block 500. The metal block 500 forms the electrical conductor 114 of the frame 106 of the power device. In one embodiment, the metal block 500 is a copper block comprising copper or a copper alloy. According to the Fig. In the embodiment shown in Figures 7A to 7G, the power stage module 100 comprises a PCB with at least one semiconductor wafer 130 embedded in the PCB between an upper and a lower surface of the PCB. The PCB has at least two layers with microvia connections and metal traces that provide electrical connections to the at least one semiconductor wafer 130 embedded in the PCB. At least some of the metal traces of the PCB extend in a direction perpendicular to the upper and lower surfaces of the PCB.

[0061] Fig. Figure 7B shows the power stage module 100 and the metal block 500 mounted on a carrier 502, for example a carrier tape. The power stage module 100 is laterally spaced from the metal block 500 when mounted on the carrier 502.

[0062] Fig. Figure 7C shows the metal block 500 and the power stage module 100 embedded in a molding compound 504 to form an encapsulated package. Any molding process typically used to form encapsulated semiconductor packages can be used, for example, injection molding, film-assisted molding, transfer molding, etc. The metal block 500 and the terminals 116, 118, 120, 122 of the power stage module 100 are not covered by the molding compound 504 on either the upper or lower surface of the encapsulated package.

[0063] Fig. Figure 7D shows the encapsulated package after removal of carrier 502.

[0064] Fig. Figure 7E shows the encapsulated package after the first terminal 124 of the passive component 102 has been connected to the output terminal 116 of the power stage module 100, and the second terminal 126 of the passive component 102 has been connected to the metal block 500, which forms the electrical conductor 114 of the frame 106. The passive component 102 has a larger footprint than the power stage module 100. The frame 106, which in this embodiment contains the molding compound 504 and the metal block 500, increases the footprint of the power stage module 100 to accommodate the mounting of the passive component 102 to the power device.

[0065] Fig. Figure 7F shows the encapsulated package during a singulation process, which separates it from other encapsulated packages produced simultaneously. Any typical singulation process, such as sawing, can be used to singulate the individual encapsulated packages. The singulation process is represented by dashed boxes in Fig. 7F shown.

[0066] Fig. Figure 7G shows one of the individual encapsulated packages. According to this embodiment, the electrically insulating material 114 of the frame 106 is a molding compound 504, the electrical conductor 112 of the frame 106 is a metal block 500 embedded in the molding compound 504, and the metal block 500 is not covered by the molding compound 504 on either the upper or lower surface of the frame 106. The power stage module 100 is embedded in the molding compound 504 such that the output terminal 116 on the upper side of the power stage module 100 is not covered by the molding compound 504, and the power terminal, ground terminal, and I / O terminals 118, 120, 122 on the lower side of the power stage module 100 are also not covered by the molding compound 504. The power stage module 100 is secured by means of the molding compound 504.The performance level module 100 and / or the molding compound 504 may have surface features, such as bumps, protrusions, dimples, etc., which aid in fastening.

[0067] As previously explained, the type of power device depends on the type of power converter. For example, the power converter may be a switched-capacitor converter, and one or more capacitors of the switched-capacitor converter may be integrated with the converter's power stage module according to the power device embodiments described herein. In another example, the power converter may be an isolated or non-isolated converter, and the passive component integrated with the power stage module may be an output inductor. The converter may be resonant or non-resonant. The power converter may contain one power stage module in the case of a single-phase converter, or more than one power stage module in the case of a multi-phase converter (e.g., one power stage module per phase), with each phase configured to contribute to the total load current.Further combinations of power stage module and passive component types can be integrated in accordance with the power device embodiments described here.

[0068] Fig. Figure 8 shows an exemplary schematic diagram of a half-bridge-type power stage 600. Such a half-bridge power device can be used in various types of converters, including but not limited to switched-mode power supplies, for example, boost converters, buck converters, buck-boost converters, flyback converters, resonant converters, etc. The power stage 600 provides one phase of the converter. The converter can be single-phase or multi-phase.

[0069] The half-bridge power stage 600 comprises a high-side switching device HS, which is coupled between an input voltage Vin and a common switching node SW, and a low-side switching device LS, which is coupled between the common switching node SW and a reference potential, for example, ground. The switching node SW is coupled to a load 602 via an output capacitor C and an output inductor L. A controller 604 sets the duty cycle of the control signal PWM for the high-side switching device HS and the low-side switching device LS in order to regulate the output voltage V0, which is applied to the load R. LA 606 driver converts the PMW control signal into a suitable voltage signal for the gates of the high-side and low-side switching devices HS and LS. The high-side switching device HS and the low-side switching device LS can be implemented using any standard type of power transistor switch typically used in the power stages of a power converter, for example, but not limited to, power MOSFETs (metal-oxide semiconductor field-effect transistors), IGBTs (insulated-gate bipolar transistors), HEMTs (high-electron-mobility transistors), etc.

[0070] The high-side switching device HS, the low-side switching device LS, and the driver 606 can be implemented on separate semiconductor chips or integrated on the same semiconductor chip. In the case of separate chips, the power stage module 100 described here comprises a first power transistor chip containing the high-side switching device HS, a second power transistor chip containing the low-side switching device LS, and a driver chip containing the driver 606. Each chip is embedded in an electrically insulating material, such as a high-density PCB. Alternatively, the high-side switching device HS, the low-side switching device LS, and the driver 606 can be integrated on the same semiconductor chip.

[0071] In any case, the electrical connections between the switching device HS, the low-side switching device LS and the driver 606 are configured such that the power stage 600 is configured as a half-bridge, as shown in Fig.Figure 8 shows these electrical connections. These electrical connections are formed by means of the power stage module 100. For example, the switched node SW output of the half-bridge 600 is electrically connected to the output terminal 116 of the power stage module 100. The input voltage Vin of the half-bridge 600 is electrically connected to the power terminal 118 of the power stage module 100. The reference terminal of the half-bridge 600 is connected to the ground terminal 120 of the power stage module 100. The input to the driver 606 is electrically connected to one of the I / O terminals 122 of the power stage module 100. The output inductor L connects the output terminal 116 of the power stage module 100, which corresponds to the switched node SW output of the half-bridge 600, electrically to the electrical conductor 112 of the frame 106.

Claims

[1] Having a power device: comprising a frame (106) comprising an electrically insulating material (112), an opening (104) in the electrically insulating material (112), and an electrical conductor (114) extending through the electrically insulating material (112); a power stage module (100) which is attached in the opening (104) in the electrically insulating material (112) and has an output terminal (116) on a first side of the power stage module (100), and a power terminal (118), a ground terminal (120) and a plurality of input / output, ‘I / O’, ​​terminals (122) on a second side of the power stage module (100), which is opposite the first side; and a passive component (102) having a first connection which is connected to the output connection (116) of the power stage module (100) and a second connection which is connected to the electrical conductor (114) of the frame (106), where the passive component (102) has a larger footprint than the power stage module (100), wherein the frame (106) increases the base area of ​​the power stage module (100) in order to accommodate the attachment of the passive component (102) to the power device, where the frame (106) has a lower connection density than the power stage module (100). [2] The power device according to claim 1, wherein the only electrical connection provided by means of the frame (106) is a vertical electrical connection for the second connection of the passive component (102) from an upper surface of the frame (106) to a lower surface of the frame (106). [3] The power device according to claim 1, wherein the frame (106) is a first printed circuit board, ‘PCB’, wherein the electrical conductor (114) of the frame (106) has one or more coated through-holes extending from an upper surface of the first PCB to a lower surface of the first PCB, and wherein the first PCB is free of metal traces extending in a direction perpendicular to the upper and lower surfaces of the first PCB. [4] The power device according to claim 3, wherein the power stage module (100) has a second PCB and has at least one semiconductor wafer embedded in the second PCB between the upper and lower surfaces of the second PCB, wherein the second PCB has at least two layers with microvia connections and metal traces which provide an electrical connection to the at least one semiconductor wafer embedded in the second PCB, and wherein at least some of the metal traces on the second PCB extend in a direction perpendicular to the upper and lower surfaces of the second PCB. [5] The power device according to claim 4, wherein the second PCB has a line / space, ‘L / S’, ratio of 75 µm / 75 µm or less, and wherein the first PCB has an L / S ratio of 150 µm / 150 µm or greater. [6] The power device according to claim 4 or 5, wherein the second PCB is fixed in the opening in the first PCB by means of an adhesive, a mechanical fastening or a soldering compound. [7] The power device according to claim 1, wherein the frame (106) is a cast-in conductor frame comprising a plurality of leads (404) embedded in a molding compound (406), and wherein the electrical conductor (114) of the frame (106) comprises one or more of the leads (404) of the plurality of leads (404) which are not covered by the molding compound (406) on either an upper surface of the cast-in conductor frame or a lower surface of the cast-in conductor frame. [8] The power device according to claim 7, wherein the power stage module (100) is embedded in the molding compound (406) of the cast-in conductor frame, wherein the output terminal (116) on the first side of the power stage module (100) is not covered by the molding compound (406), and wherein the power terminal (118), the ground terminal (120) and the plurality of I / O terminals (122) on the second side of the power stage module (100) are not covered by the molding compound (406). [9] The power device according to one of claims 1 to 2, wherein the electrically insulating material (112) of the frame (106) is a molding compound (406), wherein the electrical conductor (114) of the frame (106) is a metal block (500) embedded in the molding compound (406), and wherein the metal block (500) is not covered by the molding compound (406) on either an upper surface of the frame (106) or a lower surface of the frame (106). [10] The power device according to claim 9, wherein the power stage module (100) is embedded in the molding compound (406), wherein the output terminal (116) on the first side of the power stage module (100) is not covered by the molding compound (406), and wherein the power terminal (118), the ground terminal (120) and the plurality of I / O terminals (122) on the second side of the power stage module (100) are not covered by the molding compound (406). [11] The power device according to claim 9 or 10, wherein the metal block (500) is a copper block comprising copper or a copper alloy. [12] The power device according to any one of claims 1 to 3, wherein the power stage module (100) comprises a first power transistor plate, a second power transistor plate and a driver plate which are embedded in a PCB and configured as a half-bridge which has a switched node output which is electrically connected to the output terminal (116) of the power stage module (100), and wherein the passive component (102) is an inductor which electrically connects the switched node output to the electrical conductor (114) of the frame (106). [13] Having a performance system: a PCB; and a power device which is attached to the PCB, wherein the power device comprises: a frame (106) which comprising an electrically insulating material (112), an opening (104) in the electrically insulating material (112), and an electrical conductor (114) which extends through the electrically insulating material (112) and is connected to one or more metal pads on a first side of the PCB; a power stage module (100) which is attached in the opening (104) in the electrically insulating material (112) and which has an output terminal (116) on one side of the power stage module (100) which faces away from the PCB, and a power terminal (118), a ground terminal (120) and a plurality of input / output, ‘I / O’, ​​terminals (122) on one side of the power stage module (100) facing the PCB, which are connected to respective additional metal pads on the first side of the PCB; and a passive component (102) which is attached to the power device on a side of the power device which faces away from the PCB, wherein the passive component (102) has a first connection which is connected to the output terminal (116) of the power stage module (100), and a second connection which is connected to the electrical conductor (114) of the frame (106) such that the output connection (116) of the power stage module (100) is electrically connected to one or more metal pads on the first side of the PCB by means of the passive component (102) and the electrical conductor (114) of the frame (106), where the passive component (102) has a larger footprint than the power stage module (100), wherein the frame (106) increases the base area of ​​the power stage module (100) in order to accommodate the attachment of the passive component (102) to the power device, where the frame (106) has a lower connection density than the power stage module (100). [14] A method for manufacturing a power device, wherein the method comprises: Forming a frame (106) which has an electrically insulating material (112), an opening (104) in the electrically insulating material (112), and an electrical conductor (114) which extends through the electrically insulating material (112); Attaching a power stage module (100) in the opening (104) in the electrically insulating material (112), wherein the power stage module (100) has an output terminal (116) on a first side of the power stage module (100), and a power terminal (118), a ground terminal (120) and a plurality of input / output, ‘I / O’, ​​terminals (122) on a second side of the power stage module (100), which is opposite the first side; and Connecting a first terminal of a passive component (102) to the output terminal (116) of the power stage module (100) and a second terminal of the passive component (102) to the electrical conductor (114) of the frame (106), where the passive component (102) has a larger footprint than the power stage module (100), wherein the frame (106) increases the base area of ​​the power stage module (100) in order to accommodate the attachment of the passive component (102) to the power device, where the frame (106) has a lower connection density than the power stage module (100). [15] The method according to claim 14, wherein forming the frame (106) comprises: Forming a first printed circuit board, 'PCB', which has one or more coated through-holes extending from a top surface of the first PCB to a bottom surface of the first PCB, wherein the one or more coated through-holes form the electrical conductor (114) of the frame (106), wherein the first PCB is free of metal traces which run in a direction perpendicular to the upper and lower surfaces of the first PCB. [16] The method according to claim 15, wherein the fastening of the power stage module (100) in the opening (104) in the electrically insulating material (112) comprises: Mounting the first PCB onto a substrate; Mounting the power stage module (100) onto the carrier through the opening in the first PCB; Gluing, mechanically fastening, or soldering the power stage module (100) to the first PCB while the power stage module (100) and the first PCB are mounted on the carrier; and After gluing, mechanically fastening or soldering the power stage module (100) to the first PCB, remove the carrier from the power device. [17] The method according to claim 14, comprising forming the frame (106) and securing the power stage module (100) in the opening (104) in the electrically insulating material (112): Mounting a ladder frame onto a support, wherein the ladder frame has one or more leads (404) which form the electrical conductor (114) of the frame (106); Mounting the power stage module (100) onto the carrier, spaced laterally from one or more leads (404) of the ladder frame; Embedding one or more leads (404) of the conductor frame and the power stage module (100) in a molding compound (406) to form an encapsulated package, wherein the one or more leads (404) of the conductor frame and the terminals of the power stage module (100) are not covered by the molding compound (406) on either a top surface or a bottom surface of the encapsulated package; and After forming the cast package, remove the carrier from the cast package. [18] The method according to claim 14, comprising forming the frame (106) and securing the power stage module (100) in the opening (104) in the electrically insulating material (112): Mounting a metal block (500) onto a support, wherein the metal block (500) forms the electrical conductor (114) of the frame (106); Mount the power stage module (100) onto the carrier and spaced laterally away from the metal block (500); Embedding the metal block (500) and the power stage module (100) in a molding compound (406) to form a cast package, wherein the metal block (500) and the terminals of the power stage module (100) are not covered by the molding compound (406) on either a top surface or a bottom surface of the cast package; and After forming the cast package, remove the carrier from the cast package. [19] The method according to claim 18, wherein the metal block (500) is a copper block comprising copper or a copper alloy. [20] The method according to any one of claims 14 to 19, wherein the fastening of the power stage module (100) in the opening (104) in the electrically insulating material (112) comprises: Embedding a first power transistor chip, a second power transistor chip, and a driver chip in a PCB configured as a half-bridge, which has a switched node output that is electrically connected to the output terminal (116) of the power stage module (100); and Securing the PCB in the opening (104) in the electrically insulating material (112), wherein the passive component (102) is an inductor which electrically connects the switched node output to the electrical conductor (114) of the frame (106).

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