Packaging structure of half-bridge power module, use of packaging structure of half-bridge power module, and manufacturing method for packaging structure of half-bridge power module

Abstract

Disclosed in the present invention is a packaging structure of a half-bridge power module. The packaging structure comprises an insulating and thermal conductive plate, a multi-layer circuit board, a plastic package body and a bridge arm switch. Further disclosed in the present invention is the use of a packaging structure of a half-bridge power module in an OBC power source converter, a DCDC isolated converter, a non-isolated power source converter, a cardiac arrest awakening apparatus, and a circuit module formed by means of combining multiple half bridges such as ANPC, TNPC and Heric. Further disclosed in the present invention is a manufacturing method for a packaging structure of a half-bridge power module. The method comprises: performing assembling; providing an overflow region; and synchronously performing filling and grinding to remove the overflow region. In the present invention, a minimum size and a low impedance are achieved by means of DBC, flexible pin leading-out and welding are realized by means of a PCB, the reliability, safety and heat dissipation of modules are supported by means of a plastic packaging body, and the extension of a temperature monitoring unit and a decoupling capacitor is supported.

Description

A packaging structure, application and manufacturing method of a half-bridge power module Technical Field

[0001] The present invention relates to the field of power electronics technology, and in particular to a packaging structure of a half-bridge power module, which is used in vehicle power supplies, industrial power supplies, and medical power supplies, and a manufacturing method thereof. Background Art

[0002] Traditional small and medium power supply designs often use standard single-tube packages, such as TO247 plug-in and TO263 surface mount. These packages can be mixed and matched based on the system application to create different circuit topologies and structural layouts.

[0003] Currently, single-transistor devices are limited by their packaging and standard size, making it difficult to further improve system power density. Existing technologies have introduced top-cooled single-transistor packaging, which can achieve a balance between power density and heat dissipation to a certain extent. However, there are still problems such as large size, long circuit paths, inflexible pin configurations, and difficult insulation.

[0004] In order to cope with some specific applications, the industry has proposed some new forms of half-bridge power modules that can solve some problems in single-tube packaging.

[0005] The second aspect of the prior art proposes a top-cooled package with power and signal pins extending from the side. This package's pinout rigidly defines the pins, resulting in a relatively uniform size and lack of flexibility. The pins extend outward, increasing the loop path and reducing the safety distance from the heat sink, requiring additional insulation.

[0006] Thirdly, the existing technology also proposes that the pins adopt the straight-in form, and the power and signal pins can be directly led out from the vertical direction, which is more diverse and flexible in form than the pins on both sides. However, in fact, it is limited by the layout of the power devices on the substrate. Once the design is solidified, the lead-out method is also locked. Adjustments on the system side must accommodate the pin-out method. In addition, the straight-in pin-out often requires the use of PTH soldering technology, and the through-holes pass through each layer of PCB and avoid safety distances. It will occupy a larger PCB area and affect the utilization rate of the system PCB design. The package also needs to be installed by leading out press-fit terminals on both sides and installing them by screw press-fitting. The overall size is relatively large, and it will also cause stress on the pins of the module during installation.

[0007] Summary of the Invention

[0008] In view of this, one of the objectives of the present invention is to provide a packaging structure for a half-bridge power module. By breaking the whole into parts, the circuit structure of the half-bridge is used as a common circuit unit in various circuit applications, and the small core of the common circuit unit is optimized to the extreme and then further combined. The small core encapsulates at least two chips and the optimized electrical connection and heat dissipation structure, thereby reducing the overall size of the circuit application module and optimizing its performance.

[0009] To achieve the above objectives, the present invention provides, in a first aspect, a package structure for a half-bridge power module, comprising an insulating heat-conducting plate, a multilayer circuit board, a package filler, and a bridge arm switch, wherein the bridge arm switch comprises an upper bridge arm switch and a lower bridge arm switch, each of the upper bridge arm switch and the lower bridge arm switch comprises at least one power element, wherein the lower surface of the package structure serves as a heat dissipation surface, and the upper surface of the package structure serves as a solder pad surface;

[0010] The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the solder pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half-bridge circuit, and the packaging filling body fills the area between the insulating heat-conducting plate and the multi-layer circuit board and covers the bridge arm switch;

[0011] The pad surface is equally divided into n×m pad surface sub-areas, where n and m are both greater than or equal to 2. The pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; and the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

[0012] Preferably, the pin pads further include NC pads, NC pads being non-connected pads. NC pads do not participate in routing inside the package structure, but can be electrically connected to other pads in a fan-out form or to circuits outside the package structure.

[0013] Preferably, the power pad includes a half-bridge positive end pad, a half-bridge negative end pad and a half-bridge midpoint end pad; the half-bridge positive end pad is electrically connected to one end of the half-bridge circuit, and the half-bridge negative end pad is electrically connected to the other end of the half-bridge circuit; the circuit node between the upper arm switch and the lower arm switch of the same half-bridge circuit is the half-bridge midpoint end, and the half-bridge midpoint end pad is electrically connected to the half-bridge midpoint end.

[0014] Preferably, the pad surface has a first edge, a second edge, a third edge, and a fourth edge that are adjacent to each other in sequence; the half-bridge midpoint end pad is arranged near the first edge and is adjacent to the second edge and the fourth edge; the half-bridge negative end pad is arranged near the third edge and is adjacent to the second edge and the fourth edge; the half-bridge positive end pad is arranged between the half-bridge midpoint end pad and the half-bridge negative end pad and is adjacent to the second edge and the fourth edge.

[0015] Preferably, at least two half-bridge circuits are arranged in the packaging structure; on the pad surface, the pin pads are arranged in an array along the first direction according to the corresponding relationship between the half-bridge circuits, and the pin pads are arranged along the second direction according to the circuit function correspondence between the half-bridge midpoint pad, the half-bridge positive pad and the half-bridge negative pad; the half-bridge positive pads corresponding to the half-bridge circuits are arranged in the same row along the first direction, and the half-bridge negative pads corresponding to the half-bridge circuits are arranged in another same row along the first direction.

[0016] Preferably, at least one of the pin pads is a grid-shaped pad, and each of the grid-shaped pads includes a plurality of sub-pads arranged in an array and electrically connected to each other within the packaging structure.

[0017] Preferably, the signal loop pads are arranged in pairs or groups, each pair or group of signal loop pads are arranged in a pad surface sub-area or share a pad surface sub-area with a power pad; each power pad is arranged in one or more pad surface sub-areas; the number of pad surface sub-areas with pin pads accounts for at least two-thirds of the total number of all pad surface sub-areas.

[0018] Preferably, each pad surface area is provided with a pin pad, and the area of ​​the pin pad in each pad surface area accounts for no less than 15%.

[0019] Preferably, the power electrodes of the arm switches are electrically connected through a multilayer circuit board, so the arm switches only need to be fixed on the insulating heat conductive plate by thermally conductive glue, and the power electrodes are arranged on the side facing the multilayer circuit board.

[0020] Preferably, the pin pad further includes a sink pad, the sink pad is electrically connected to the heat dissipation surface, and the sink pad is used to electrically connect the heat dissipation surface and an electrostatic potential.

[0021] Preferably, the insulating heat-conducting plate is a copper-clad ceramic substrate; the upper bridge arm switch and the lower bridge arm switch corresponding to the same half-bridge circuit are respectively arranged on a group of switch copper-clad areas on the insulating heat-conducting plate, and the switch copper-clad areas include an upper switch copper-clad area and a lower switch copper-clad area. The upper bridge arm switch is electrically connected to the upper switch copper-clad area, and the lower bridge arm switch is electrically connected to the lower switch copper-clad area; the upper switch copper-clad area and the lower switch copper-clad area are arranged adjacent to each other, and the corresponding edges of the upper switch copper-clad area and the lower switch copper-clad area are arranged in a serrated and zigzag manner when they are adjacent to each other.

[0022] Preferably, the packaging structure further includes an electrical connection column, both ends of which are electrically connected to the insulating heat conducting plate and the multilayer circuit board respectively; the packaging filling body covers the electrical connection column; and at least one of the electrical connection columns is located at a tooth-shaped zigzag setting.

[0023] Preferably, the multilayer circuit board is a first PCB board, and the insulating heat-conducting board is a second PCB board; the second PCB board includes at least two wiring layers and at least one insulating dielectric layer; the thermal conductivity coefficient of the insulating dielectric layer of the second PCB board is greater than 1.

[0024] Preferably, the bridge arm switch includes at least one of a MOS switch, an IGBT element with an anti-parallel diode, a thyristor and a DIO diode.

[0025] Preferably, the bridge arm switch is a third-generation semiconductor device, namely, comprising at least one of a SiC device and a GaN device. Due to the high space utilization of the packaging structure provided by the present invention, the advantages of the small size of third-generation semiconductor devices can be maximized. In the future, as technology advances and fourth or even fifth-generation semiconductor devices emerge, the package structure's volume can be further reduced to match the package resistance to the device's Rdson.

[0026] Preferably, the bridge arm switch is a vertical device, with power electrodes of different electrical properties provided on the upper surface (facing the insulating heat-conducting plate) and lower surface (facing the multilayer circuit board). The upper surfaces of the two devices are welded to the conductive wiring layer on the surface of the insulating heat-conducting plate, achieving both electrical and thermal interconnection. The insulating heat-conducting plate wiring layer and the multilayer circuit board wiring layer are electrically interconnected via electrical connection posts, etc., leading the power electrodes on the upper surfaces of the devices to the module electrodes. The corresponding electrical connection posts on the upper surfaces of the two devices are placed in the area between the two devices to reduce the size of the module.

[0027] Preferably, the packaging structure further includes an active temperature signal element, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad;

[0028] The active temperature signal element includes a temperature measurement unit, a signal processing unit, an output enable unit and an output switch device; one end of the temperature measurement unit is set to be grounded; the temperature measurement unit, the signal processing unit, the output switch device and the temperature signal pad are connected in series in sequence; the output switch device has a first end, a second end and a control end, the first end is electrically connected to the output end of the signal processing unit, and the second end is electrically connected to the temperature signal pad; the output enable unit controls the control end by comparing the potentials of the first end and the second end.

[0029] Preferably, the packaging structure also includes a temperature-sensitive Zener diode, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad; one end of the Zener diode is set to be grounded, and the other end is electrically connected to the temperature signal pad.

[0030] The purpose of providing the above-mentioned active temperature signal elements or temperature-sensitive Zener diodes (collectively referred to as temperature signal elements) is to enable, when multiple package structures are used in parallel, the corresponding temperature signal elements to be connected in parallel in an external circuit (i.e., the temperature signal pads that output the temperature signal are electrically connected to the same parallel circuit node), so that the temperature signal output corresponds to the highest temperature among the various package structures. When the package structures equipped with the active temperature signal elements are used in parallel, the corresponding active temperature signal elements can be connected in parallel. When the package structures equipped with the temperature-sensitive Zener diodes are used in parallel, the parallel circuit node of each temperature signal pad in the external circuit can be electrically connected to the power supply voltage terminal (VCC terminal) via a pull-up resistor.

[0031] Preferably, a packaging filling groove is opened on the edge of the multilayer circuit board; and the packaging filling body fills the packaging filling groove.

[0032] Preferably, a side surface of the packaging filling body is provided with a creepage bulge or a creepage groove.

[0033] Preferably, the side surface of the packaging filling body is provided with a creepage protrusion or a creepage groove with a horizontal extension length of not less than 1 mm, and the actual creepage distance increase value is twice the horizontal extension length.

[0034] Preferably, the thickness of the exposed portion of the side of the multilayer circuit board does not exceed 1mm. Since the CTI constant of general encapsulation fillers can reach 400 or even 600 or above, reducing the thickness of the exposed portion of the side of the multilayer circuit board correspondingly increases the proportion of the encapsulation filler surface in the creepage distance of the module side. With the same module thickness (for example, 4mm) and the same side creepage distance, the device's voltage resistance can be further improved, enabling the device to operate in application scenarios with a DC voltage limit of 800V or even above 1200V.

[0035] Preferably, a thick thermally conductive metal layer is further provided on the bottom surface of the insulating thermally conductive plate, and the encapsulating filling body covers the side surfaces of the thick thermally conductive metal layer.

[0036] Preferably, the packaging structure further comprises a fixing column, both ends of which are fixedly connected to the insulating heat conducting plate and the multi-layer circuit board respectively.

[0037] Preferably, the insulating heat-conducting plate is divided into four quadrants in the horizontal direction, namely, left front, left rear, right front, and right rear. At least one fixing column is provided between the insulating heat-conducting plate and the multi-layer circuit board corresponding to each quadrant.

[0038] Preferably, the multilayer circuit board is electrically connected to the fixing column and the power element respectively through welding, the height of the fixing column is Hpole, the sum of the thickness of the power element and its front electrode is Hdie, Hdie-Hpole≥20μm. Since the smaller the welding distance of the power element, the smaller the parasitic parameters of the circuit, and the height tolerance of the welding surface needs to be considered during welding, setting the height of the fixing column slightly lower can accommodate more solder here, thereby achieving better tolerance absorption function.

[0039] Preferably, the area of ​​the steel mesh opening corresponding to the solder provided on the fixing column in the welding process is not less than 120% of the welding area of ​​the top end of the fixing column, so as to provide more solder on the welding surface.

[0040] Preferably, the total welding area of ​​the top end of the fixing column is not less than 2% of the area of ​​the insulating heat conducting plate.

[0041] Preferably, the multilayer circuit board includes at least four wiring layers; each of the wiring layers is provided with a DC-wiring area, a DC+ wiring area and a SW wiring area arranged in sequence in one direction, or each of the wiring layers is provided with a DC+ wiring area, a DC- wiring area and a SW wiring area arranged in sequence in one direction; the four wiring layers include a first wiring layer and a second wiring layer, the first wiring layer and the second wiring layer are adjacent, the DC+ wiring area arranged in the first wiring layer is a large-area DC+ wiring area, the DC- wiring area arranged in the second wiring layer is a large-area DC- wiring area, and at least 10% of the projections of the large-area DC+ wiring area and the large-area DC- wiring area overlap with each other.

[0042] Preferably, the packaging structure also includes a plurality of electrical connection columns, the two ends of which are electrically connected to the insulating heat conductive plate and the multi-layer circuit board respectively; the packaging filling body covers the electrical connection columns; the power element includes at least one vertical power chip; and the electrical connection columns are arranged in parallel between the power elements.

[0043] Preferably, the electrical connection column includes a SW end electrical connection column, the SW end electrical connection column is electrically connected to the SW wiring area, the position corresponding to the SW end electrical connection column in the multi-layer circuit board is an avoidance area, at least one of the DC+ wiring areas is arranged to bypass the avoidance area, or at least one of the DC- wiring areas is arranged to bypass the avoidance area.

[0044] Preferably, when at least one of the DC+ wiring areas is arranged to bypass the avoidance area, the DC+ wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pad corresponding to the DC+ wiring area is a long strip across the avoidance area; or, when at least one of the DC- wiring areas is arranged to bypass the avoidance area, the DC- wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pad corresponding to the DC- wiring area is a long strip across the avoidance area.

[0045] Preferably, the packaging structure further includes at least one temperature sampling element, which is arranged between the upper arm switch and the lower arm switch in the direction of the connection line between the upper arm switch and the lower arm switch, and the temperature sampling element is arranged on one side of the multilayer circuit board in a direction perpendicular to the connection line between the upper arm switch and the lower arm switch.

[0046] Preferably, the power element comprises at least one third generation power semiconductor element or low withstand voltage silicon power semiconductor element, or the Rsp of the power element does not exceed 2 mOhm / cm 2 , the operating frequency of the board bridge power module is at least 100 kHz.

[0047] Preferably, the power element includes at least two planar power semiconductor elements, and the aspect ratio of the planar power semiconductor elements is at least 1.5.

[0048] Preferably, the at least two planar power semiconductor devices are arranged in parallel with their long sides and are interconnected by points to form at least one bridge arm. The multilayer circuit board includes a SW wiring area, a DC+ wiring area and a DC- wiring area, and the SW wiring area is arranged between the DC+ wiring area and the DC- wiring area.

[0049] Preferably, at least one of the DC-wiring area, the DC+ wiring area and the SW wiring area is provided with an exhaust hole, and the diameter of the exhaust hole is greater than 0.1 mm.

[0050] Preferably, the packaging structure further includes at least two bridge arm decoupling capacitors, the bridge arm decoupling capacitors are arranged at positions avoiding the insulating heat conducting plate, and the bridge arm decoupling capacitors are arranged in a straight line.

[0051] Preferably, the power element includes at least four planar power semiconductor elements, which are arranged in 2 rows and 2 columns; the packaging structure also includes a temperature sampling unit, which is arranged in the middle of the at least four planar power semiconductor elements.

[0052] Preferably, the packaging structure further includes a high-voltage isolation drive component, which is arranged on a multi-layer circuit board and is arranged on one side of the insulating heat-conducting plate and avoids the insulating heat-conducting plate.

[0053] Preferably, the packaging structure further comprises a temperature averaging plate, which is arranged on the heat dissipation surface, and is connected to the insulating heat conducting plate with low thermal resistance.

[0054] Preferably, the encapsulated filling body covers the edges of the temperature homogenizing plate and the covering thickness is at least 0.4 mm.

[0055] Preferably, the packaging structure further includes a fixing column, and two ends of the fixing column are fixedly connected to the temperature dispersion plate and the multi-layer circuit board respectively.

[0056] Preferably, the temperature homogenizing plate is arranged outside the packaging filling body.

[0057] Preferably, an isolation groove is provided on the pad surface of the multilayer circuit board, the width and depth of the isolation groove are both not less than 1 mm, and the isolation groove is used to increase the creepage distance between the high-voltage side and the low-voltage side.

[0058] Preferably, a plurality of isolation grooves are arranged side by side.

[0059] Preferably, the high-voltage isolation driver assembly includes at least two driver chips; the driver chips are electrically connected via bonding wires, or the driver chips are planar driver chips and are electrically connected via a multi-layer circuit board.

[0060] Preferably, the packaging structure further includes an electrical connection post and a current sampling winding, wherein the current sampling winding is provided with at least one turn around the electrical connection post, the current sampling winding is used to sample the high-frequency current passing through the electrical connection post, and the current sampling winding is electrically connected to a current sampling circuit.

[0061] Preferably, the current sampling winding is arranged in a multi-layer circuit board, or is preformed together with the electrical connection column to form an assembly.

[0062] Preferably, the current sampling circuit is provided with a correction function.

[0063] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, comprising the following steps:

[0064] Welding a plurality of the packaging structures onto the same PCB substrate;

[0065] A fixed housing and a common heat sink are provided, wherein the fixed housing is used to fix the common heat sink, and the fixed housing includes a cover plate located on the back side of the PCB substrate;

[0066] A pressure ejector pin is provided between the cover plate and the PCB substrate, wherein the position of the pressure ejector pin corresponds to the packaging structure;

[0067] The common heat sink is pressed onto a plurality of packaging structures through the fixed housing. During the pressing, the PCB substrate is deformed by the pressure pins so as to absorb the tolerance of each packaging structure in the thickness direction.

[0068] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, comprising the following steps:

[0069] Welding a plurality of the packaging structures onto the same PCB substrate;

[0070] A fixed shell and liquid-cooled radiators corresponding in number to the packaging structures are provided. The fixed shell is used to press and fix the liquid-cooled radiators to the corresponding packaging structures. The fixed shell includes a heat dissipation liquid pipeline, an interface hose and a pressure elastic member. The interface hose is used to connect the liquid path between the heat dissipation liquid pipeline and the liquid-cooled radiators, so that the heat dissipation liquid pipeline and each liquid-cooled radiator form a connected integral liquid path.

[0071] The liquid-cooled radiator is pressed and fixed on multiple packaging structures through the fixed shell. During pressing, the fixed shell applies pressure in the pressing and fixing direction to the liquid-cooled radiator through the pressure elastic part. The pressure elastic part and the interface hose absorb the tolerance of each packaging structure in the thickness direction through deformation.

[0072] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to an on-board OBC power converter, wherein the on-board OBC power converter comprises a substrate and at least two of the half-bridge power modules, wherein at least one power pin between the two half-bridge modules is electrically short-circuited via a system-side multi-layer circuit board. The substrate comprises a first component area, a second component area, and a third component area, which are arranged in sequence. The first component area is provided with a capacitor and a controller, the second component area is provided with the half-bridge power module, the heat dissipation surface of the half-bridge power module is provided with a heat sink, and the third component area is provided with a transformer and an inductor. The winding of the inductor is integrated into the substrate, or the winding of the inductor is independently heat-dissipated and insulated from the iron core by cavity-encapsulated insulating thermal adhesive. The driving component corresponding to the bridge arm switch is provided on the other side of the substrate corresponding to the half-bridge power module.

[0073] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a DCDC isolation converter, wherein the DCDC isolation converter includes a substrate, a transformer core, and at least one half-bridge power module. The half-bridge power module is an input side module and / or an output side module. The transformer core is buckled onto the substrate, and the windings corresponding to the transformer core are integrated into the substrate. The input side module and the output side module are respectively arranged on both sides of the transformer core. The heat dissipation surfaces of at least a portion of the half-bridge power modules share a heat sink, and an insulating heat conductor is provided between the transformer core and the heat sink.

[0074] Preferably, the DCDC isolation converter further includes a secondary insulation processing structure, and the secondary insulation processing structure is a secondary plastic packaging body or a glue filling structure.

[0075] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a non-isolated power converter, wherein the non-isolated power converter includes a substrate, an inductor element, and at least one half-bridge power module;

[0076] The half-bridge power module is arranged on a substrate;

[0077] The inductor element is arranged in parallel with the assembly of the half-bridge power module and the substrate, or the inductor element is arranged in parallel with the half-bridge power module on the substrate;

[0078] The half-bridge power module and the inductive element share a heat sink, and the inductive element and the heat sink are directly provided with insulating heat conducting members.

[0079] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, and the half-bridge power module is applied to a cardiac arrest awakening device, wherein the cardiac arrest awakening device includes a housing, a first PCBA component layer, a second PCBA component layer and a filling glue, wherein the first PCBA component layer and the second PCBA component layer are stacked in the housing, and the filling glue is filled in the gap between the housing, the first PCBA component layer and the second PCBA component layer; the first PCBA component layer includes a power supply element and a power supply drive element, and the second PCBA component layer includes at least one half-bridge power module, and at least one half-bridge power module is used to generate a high-voltage pulse output, and the heat dissipation surface of the half-bridge power module is in contact with the housing.

[0080] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a large IPM module, comprising the following steps:

[0081] The heat dissipation surfaces of the multiple packaging structures are fixedly connected to the radiator; soldered to the first PCB substrate through SMD; and module circuit elements are set on the other side of the first PCB substrate; the module circuit elements include at least one of a control unit, a driving unit and a decoupling capacitor.

[0082] Preferably, the large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting multiple bidirectional switch bridge arms in parallel.

[0083] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to a large IPM module, comprising the following steps:

[0084] The heat dissipation surfaces of the multiple packaging structures are fixedly connected to a heat sink; soldered to a first PCB substrate via SMD; a second PCB substrate is provided, and module circuit elements are arranged on the second PCB substrate; the module circuit elements include at least one of a control conductor, a drive unit, and a decoupling capacitor; the second PCB substrate and the first PCB substrate are electrically connected via elastic pins.

[0085] Preferably, the large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting multiple bidirectional switch bridge arms in parallel.

[0086] Preferably, the method further comprises the following steps:

[0087] Decoupling capacitors are arranged between and outside the packaging structure, and the decoupling capacitors are arranged on the heat sink through a thermal pad and are electrically connected to the first PCB substrate;

[0088] A Vbus capacitor is provided on the first PCB substrate; the Vbus capacitor is provided adjacent to the assembly of the decoupling capacitor, the packaging structure and the heat sink.

[0089] Preferably, the method further comprises the following steps:

[0090] Disposing a decoupling capacitor and elastic pins on a surface of the first PCB substrate facing the second PCB substrate;

[0091] A cover plate is installed on the first PCB substrate, the cover plate covers the decoupling capacitor, and the upper ends of the elastic pins extend out of the cover plate.

[0092] Preferably, the method further comprises the following steps:

[0093] A suspended pad is provided on a surface of the first PCB substrate facing the second PCB substrate, the suspended pad being adjacent to a circuit node pad corresponding to a circuit node corresponding to a pin of a decoupling capacitor, the decoupling capacitor and the suspended pad are electrically connected, and a disconnection is maintained between the suspended pad and the corresponding circuit node pad;

[0094] The leakage current of the package structure is tested, and after the test is passed, the suspended pad is electrically connected to the corresponding circuit node pad.

[0095] Another aspect of the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, wherein the half-bridge power module is applied to an ANPC circuit, wherein the ANPC circuit includes a plurality of ANPC subunits arranged in parallel, wherein the ANPC subunits include a first half-bridge power module, a second half-bridge power module, and a third half-bridge power module, wherein the bridge arm switches of the first half-bridge power module and the second half-bridge power module are both IGBT elements with anti-parallel diodes, and the first half-bridge power module and the second half-bridge power module are connected in series;

[0096] The bridge arm switch of the third half-bridge power module is a MOS switch or an IGBT element of an anti-parallel diode. The half-bridge positive end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the second half-bridge power module.

[0097] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, and the half-bridge power module is applied to a TNPC circuit. The TNPC circuit includes multiple TNPC sub-units arranged in parallel, and the TNPC sub-units include a first half-bridge power module and a second half-bridge power module. The second half-bridge power module is a bidirectional switch module, and the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the half-bridge positive end pad of the bidirectional switch module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the bidirectional switch module is grounded.

[0098] On the other hand, the present invention provides an application of the packaging structure of the above-mentioned half-bridge power module, and the half-bridge power module is applied to a Heric circuit, and the Heric circuit includes a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, and the third half-bridge power module is a bidirectional switch module, and the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the first half-bridge power module and the second half-bridge power module are connected in parallel through the half-bridge positive end pad and the half-bridge negative end pad, and the bidirectional switch module is bridged between the half-bridge midpoint end pad corresponding to the first half-bridge power module and the half-bridge midpoint end pad of the second half-bridge power module.

[0099] Another aspect of the present invention provides a method for manufacturing a packaging structure of a half-bridge power module, comprising the following steps:

[0100] S1: Assemble and fix the insulated heat conducting plate, multi-layer circuit board and bridge arm switch;

[0101] S2: setting an overflow area below the insulating heat conducting plate, and filling the space between the insulating heat conducting plate and the multilayer circuit board and the overflow area with a packaging filler simultaneously, so that the mold flow impact of the upper and lower surfaces of the insulating heat conducting plate during packaging filling is offset, and the space between the insulating heat conducting plate and the multilayer circuit board and the overflow area forms a packaging filling body;

[0102] S3: removing the packaging filling body in the overflow area by grinding;

[0103] The bridge arm switch includes an upper bridge arm switch and a lower bridge arm switch, each of the upper bridge arm switch and the lower bridge arm switch includes at least one power element, the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface;

[0104] The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multilayer circuit board is arranged at the top of the packaging structure and one surface of the multilayer circuit board is the solder pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multilayer circuit board, and the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit.

[0105] Preferably, the pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

[0106] Preferably, the thickness of the packaging filling body in the overflow area is not less than 0.3 mm.

[0107] Preferably, the heat dissipation surface is the back side of an insulating heat conducting plate, and the back side of the insulating heat conducting plate is provided with back side copper cladding. In step S1 , the thickness of the back side copper cladding is not less than 150 μm.

[0108] Preferably, step S3 further includes: thinning the back copper cladding by grinding.

[0109] Preferably, the front side of the insulating heat conducting plate is provided with front copper cladding. In step S1, the thickness of the front copper cladding is smaller than that of the back copper cladding, and the difference between the thickness of the front copper cladding and the thickness of the back copper cladding is at least 50 μm.

[0110] Preferably, after step S3 , the thickness tolerance of the packaging structure does not exceed 100 μm.

[0111] The beneficial effects of the present invention are:

[0112] (1) The present invention provides pads on the top PCB, so that pins can be directly led out from the vertical direction of the power module without having to lead out to the sides, thereby reducing the size of the module and the pin loop path. Each part of the upper surface can be used as a pad area, which has a more flexible pin-out method; and the pads are welded to the system application board through the SMT method, which is easy to produce and implement; by uniformly distributing the pads on the upper surface and controlling the total area, the welding strength is improved, and the risk of SMD solder joint failure caused by displacement due to differences in thermal expansion is avoided;

[0113] (2) The present invention only requires the application of thermal conductive silicone grease between the device and the heat sink, and no additional insulation treatment is required, making it easy to install. In addition, after installation, the solder pad is free of mechanical stress, and the side of the DBC board facing the module can cooperate with the PCB board to form a 3D packaged electrical connection structure, achieving the smallest size and low impedance. The area utilization rate of this half-bridge module is extremely high. In actual design, for example, 650V 41mOhm and 99mOhm half-bridges, the total size is only 44% and 30% of the existing technology using the packaging design of the present invention. Since the thickness of the present invention can be used as insulation, it has a larger creepage distance, while ensuring the advantages of insulation, heat dissipation, and high reliability. Compared with the traditional leadframe SMD solution, its thickness utilization rate is at least 1 to 2 mm better, that is, to meet the same insulation requirements, its thickness can be reduced by 1 to 2 mm. This is extremely valuable in the trend of increasingly tight space resources.

[0114] (3) The present invention can take into account the system design of the power module. By modularly packaging the common circuit unit, namely the half-bridge circuit structure, a set of standard power module design concepts is formed, and it can be compatible with different types of power devices and sizes.

[0115] (4) The present invention strengthens the fixed connection between the insulating heat-conducting plate and the multi-layer circuit board through fixed columns or offsets the mold flow impact force through the overflow area, thereby avoiding problems such as solder joint tearing caused by mold flow impact in the packaging filling process; further reduces the parasitic parameters of the module through the wiring setting of the multi-layer circuit board; increases the creepage distance by grooving or setting an external convex structure, thereby improving the module's voltage resistance performance, and can integrate high-voltage isolation drive components internally, further simplifying the overall module structure when using the power module. BRIEF DESCRIPTION OF THE DRAWINGS

[0116] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0117] 1A to 4X are schematic diagrams of a first embodiment of the present invention;

[0118] 5A to 5C are schematic diagrams of a second embodiment of the present invention;

[0119] 6A and 6I are schematic diagrams of a third embodiment of the present invention;

[0120] 7A to 7F are schematic diagrams of a fourth embodiment of the present invention;

[0121] 8A to 9D are schematic diagrams of a fifth embodiment of the present invention;

[0122] 9E to 9G are schematic diagrams of a sixth embodiment of the present invention;

[0123] 10A to 10B are schematic diagrams of a seventh embodiment of the present invention;

[0124] 11A to 11E are schematic diagrams of an eighth embodiment of the present invention;

[0125] 12A to 12N are schematic diagrams of a ninth embodiment of the present invention;

[0126] 13A to 13G are schematic diagrams of a tenth embodiment of the present invention;

[0127] 14A to 14F are schematic diagrams of an eleventh embodiment of the present invention;

[0128] FIG15 is a schematic diagram of a twelfth embodiment of the present invention. DETAILED DESCRIPTION

[0129] One of the core aspects of this invention is to provide a packaging structure for a half-bridge power module. By breaking down the entire structure into smaller components, the half-bridge circuit structure serves as a common circuit unit in various circuit applications. The small cores of these common circuit units are optimized to their maximum potential and then further combined. These small cores encapsulate at least two chips along with optimized electrical connections and heat dissipation structures, thereby reducing the overall size of the circuit application module and optimizing its performance. Another aspect of the invention provides applications for the packaging structure of this half-bridge power module.

[0130] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0131] Example 1

[0132] As shown in Figures 1A and 1B, the packaging structure of a half-bridge power module disclosed in this embodiment includes an insulating heat-conducting plate 14 (generally a copper-clad ceramic substrate, i.e., DBC, and the DBC may be provided with metal layers on its upper and lower surfaces), a multi-layer circuit board 12 (generally a printed circuit board, i.e., PCB), a plastic package body 13 and at least two bridge arm switches, the bridge arm switches including an upper bridge arm switch and a lower bridge arm switch, the lower surface of the packaging structure is a heat dissipation surface, the upper surface of the packaging structure is a pad surface (a pin pad 11 is provided on the pad surface), and the side surface of the packaging structure is mainly an insulating surface.

[0133] The insulating heat-conducting plate 14 is arranged at the bottom of the packaging structure, the multi-layer circuit board 12 is arranged at the top of the packaging structure, the bridge arm switch is arranged between the insulating heat-conducting plate 14 and the multi-layer circuit board 12, the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half-bridge circuit, and the plastic package 13 fills the area between the insulating heat-conducting plate 14 and the multi-layer circuit board 12 and covers the bridge arm switch; as shown in Figure 1C, the pads of the half-bridge power module 1 of this embodiment are welded to the customer's mainboard 2 by SMT, which is easy to produce and implement; due to the insulation function of DBC, only thermal grease needs to be applied between the half-bridge power module 1 and the heat dissipation structure such as the radiator (not shown in the figure), and no additional insulation treatment is required, which is easy to install; and the packaging structure of this embodiment minimizes the length of the electrical circuit path within the module as much as possible, while maximizing the creepage distance on the side of the module.

[0134] Specifically: As shown in Figures 2A to 2D, the half-bridge power module includes a half-bridge circuit consisting of a first power chipset (i.e., an upper bridge arm switch, QH) and a second power chipset (i.e., a lower bridge arm switch, QL). The power lead of the half-bridge circuit includes the first chip drain (DC+), the half-bridge midpoint (i.e., the lead formed by the electrical connection between the first power chip source and the second power chip drain, SW), and the second power chip source (DC-). Traditional packaging has to sacrifice electrical performance and size in order to take into account both the internal chip arrangement and external pins of the module. Since this embodiment uses DBC (i.e., an insulating heat conductive plate 14) and PCB (i.e., a multi-layer circuit board 12) 3D packaging to achieve power interconnection, both the DBC side facing the power chip and the PCB can be provided with an electrical connection structure, so there is more flexibility to achieve a better arrangement. The first power chip and the second power chip can be placed according to the path with the least current, and the structural diagram is almost the same as the circuit diagram. Short, wide leads minimize parasitic resistance and inductance, enabling higher currents and faster switching speeds. This also minimizes the overall DBC size by reducing the footprint of the leads. Multilayer PCBs offer flexible and effective pinouts for low-loop, high-current applications. This allows for optimal routing of both internal and external wiring without trade-offs, truly achieving optimal performance.

[0135] In a preferred embodiment, the two bridge arm switches of the half-bridge power module are arranged in parallel and close to each other on the DBC to form a DBC power zone from one side to the other, and are electrically interconnected through the DBC or PCB power.

[0136] The power leads from the chipset's surface electrodes are interconnected using metal wires or copper clips (collectively referred to as interconnects 15). These interconnects can be connected via the metal wiring layer on the DBC surface, initially electrically connecting to the DBC metal wiring layer. The DC+, DC-, and SW electrodes are then connected from the DBC to the multilayer PCB via metal (such as copper pillars, plated vias, etc., collectively referred to as electrical connection posts 16). These connections are then electrically connected to the SMD pads via the PCB metal layer, as shown in Figure 1D.

[0137] In a preferred embodiment, the driving signal is distributed on one or both sides of the DBC power region to form a signal region.

[0138] In a preferred embodiment, the power zones are arranged in the following order: DC+, first power chipset, SW interconnect, SW pillar, second power chipset, DC- interconnect, DC- pillar. This achieves the shortest and smallest power interconnects. Preferably, the SW pillars and SW lead wires are placed horizontally and crosswise to achieve uniform current distribution.

[0139] In a preferred embodiment, the chipset surface electrodes are directly connected to the PCB without transitioning through the DBC metal layer. The power interconnects between the two chipsets are formed through the PCB's multi-layer metal layers. The electrodes of the arm switches are first electrically connected through the PCB's multi-layer metal layers, forming a half-bridge circuit. The DC+, DC-, and SW pins are then electrically connected to the corresponding SMD pads through the PCB metal layers.

[0140] In a preferred embodiment, the drive signal is also directly electrically coupled to the PCB without transitioning through the DBC metal layer.

[0141] In some other embodiments, the electrical interconnection between the chipset and the PCB can be achieved through copper pillars, solder balls, copper sheets, etc. (collectively referred to as electrical connection pillars 17) on the surface of the chipset, as shown in Figure 1E. Alternatively, the electrical interconnection between the chipset and the PCB can also eliminate intermediate structures such as electrical connection pillars 17 and be achieved directly through electroplating between the surface of the chipset and the PCB; the direct electrical interconnection between the chipset and the PCB can further reduce the height of the half-bridge power module 1.

[0142] The power chipset can flexibly select chip types. The first power chipset and the second power chipset each contain at least one chip, and the chip type can be:

[0143] 1: IGBT contains anti-parallel diode, MOS tube (such as Si MOS, SiC MOS, GaN MOS, etc.); diode or thyristor, etc.

[0144] The power chips can be selected from the same type of devices, or the above devices can be combined as needed. Typically, the same type of devices are selected, such as:

[0145] 1: Half-bridge IGBT with anti-parallel diode - half-bridge A type;

[0146] 2: Half-bridge Si MOSFET; ——Half-bridge B type;

[0147] 3: Half-bridge SiC MOSFET; ——Half-bridge C type;

[0148] 4: Half-bridge GaN MOSFET; ——Half-bridge D type;

[0149] 5: Half-bridge Dio - half-bridge E type;

[0150] Different types of devices can also flexibly select chip specifications. Typical specifications include voltage levels of 100V to 6500V and currents of 5A to 500A.

[0151] Among them, the circuit diagram and half-bridge power module layout schematic corresponding to the half-bridge B / C type are shown in Figures 2A and 2B, the circuit diagram and half-bridge power module layout schematic corresponding to the half-bridge A type are shown in Figures 2C and 2D, the circuit diagram corresponding to the half-bridge D type is the same as the half-bridge B / C type, and the half-bridge power module layout schematic corresponding to the half-bridge D type is shown in Figure 2E.

[0152] In some other embodiments, the power chipset may also be a horizontal device, in particular a GaN device.

[0153] In some other embodiments, the half-bridge connection of the chip can be in-phase series connection, or in-phase series connection (including common source series connection and common drain series connection or equivalent meanings), or in-phase parallel connection or in-phase parallel connection.

[0154] In a preferred embodiment, as shown in Figures 2F, 2G, and 2H, the intersection of the two larger copper clad areas corresponding to the two power chipsets on the DBC, i.e., between the two power chipsets, is typically located in the middle of the DBC. The edges of the two copper clad areas at this intersection are zigzag, forming interlocking serrated edges. This ensures that a portion of the copper clad area is always provided at each straight position in the middle of the DBC, thereby increasing the DBC's strength and bending resistance, and preventing DBC breakage during welding or assembly. Electrical connection posts 16 can be welded to the copper teeth at the serrated edges, eliminating the space required for separate placement of electrical connection posts 16 and further reducing the area of ​​the DBC.

[0155] For applications with less stringent heat dissipation requirements, the DBC can be replaced by a second PCB comprising at least two wiring layers and at least one insulating dielectric layer; the insulating dielectric layer has a thermal conductivity greater than 1, providing thermal conductivity. The outermost wiring layer of this second PCB (i.e., the heat dissipation surface) is an electrostatic potential, electrically connected to either the positive or negative half-bridge terminals. This reduces parasitic common-mode capacitance between the half-bridge trip potential terminal and the heat sink, thereby minimizing common-mode interference. In some applications, such as using a half-bridge power module in an internally air-cooled power electronic converter, where the heat sink is connected to power ground, safety insulation between the module's internal components and the heat sink is not required.

[0156] In a preferred embodiment, multiple chips are first soldered to a DBC. Electrical connection posts 17 and 16 are then implanted onto the chips and DBC copper clad areas by soldering or electroplating, and then soldered to the PCB. The chips can be soldered using silver sintering or a high-remelting-temperature solder such as high-temperature solder.

[0157] This embodiment can use SMD LGA pins for easy application. However, due to the integration of more functions, the size of the half-bridge power module is thicker and larger than that of traditional LGA SMD components. In addition, after the SMD pins are soldered to the customer's mainboard 2 (generally a PCB), the solder is very thin, usually less than 0.2mm. As a result, when the module is thermally expanded and contracted, the difference in thermal expansion between the module and the customer's mainboard 2 causes displacement, and there is a lack of buffer space, thus causing the risk of SMD solder joint failure. To improve strength and reliability, this embodiment avoids the above risks by evenly distributing the pads and increasing the total area of ​​the pads.

[0158] The pad surface is equally divided into n×m pad surface sub-areas, where n and m are both greater than or equal to 2. In this embodiment, n and m are both 3 as an example. The pin pads are evenly distributed in each pad surface sub-area, and the pin pads include the half-bridge positive end pad (corresponding to DC+), the half-bridge negative end pad (corresponding to DC-), the half-bridge midpoint end pad (corresponding to SW) and the signal loop pad (the first power chipset corresponds to HG and HS, and the second power chipset corresponds to LG and LS); the signal loop pads corresponding to the same bridge arm switch are set in the same pad surface sub-area, so there are at least 7 pads in total. In some other embodiments, the signal loop pads can also include temperature signal pads of temperature signal elements (i.e., NTC loop pads, at least one pair when set separately, and the embodiment of the half-bridge power module with temperature signal elements is referred to Example 3), i.e., there are at least 9 pads in total; in some other embodiments, the module does not require the lead-out of the bridge arm midpoint end, so there are at least 6 pads. In some other embodiments, the module half-bridge is connected in parallel, so there are at least 6 pads.

[0159] While meeting safety distance requirements, the pad pinout can be flexibly adjusted based on system requirements. As shown in Figure 3A, two pairs of signal loop pads are arranged in the left column, and three power pads are arranged at the junction of two pad surface areas in the middle and right columns, respectively. In some other embodiments, the SW and signal loop pads can also be placed in the same column, opposite the pad column formed by the power pads. Within the nine-square grid of pad surface areas divided by the PCB pad surface, at least five squares contain complete, independent pads or partial pads (at least half of the pad surface area). In this case, the pin pads are considered to be evenly distributed within each pad surface area to ensure uniform mechanical strength across the entire PCB. The total area of ​​all pads accounts for no less than 15% of the PCB area. In a preferred embodiment, each pad surface area is provided with pads, and the pads in each pad surface area occupy no less than 15% of the pad surface area, and the total area of ​​all pads accounts for no less than 30% of the PCB area.

[0160] In another preferred embodiment, each power pad (DC+ / DC- / SW is collectively referred to as a power pad) or a pair of signal loop pads (signal loop pads corresponding to the bridge arm switch drive circuit, signal loop pads corresponding to the temperature signal element, etc., usually arranged in pairs) can also be respectively arranged in the middle of the pad surface area. Sometimes the number of pad surface areas is more than the number of power pads or signal loop pad pairs required to be set, then additional unconnected pads (i.e., NC pads, Non-Connection pads) can be introduced to meet the coverage of the grid. The minimum size of the NC pad is the same as the size of the signal loop pad, as shown in FIG3B. In the embodiment shown in FIG3B, the NC pad may not be electrically connected to the metal network to ensure the safety distance between the electrodes. In some other embodiments, the NC pad can be further electrically connected to at least one power pad through a fan-out metal part, as shown in Figures 3E and 3F. The NC pads in the middle column in Figure 3E are electrically connected to each other and then to an electrostatic pad. The NC pads in the middle column in Figure 3F are electrically connected to the power pads at corresponding positions in the right column.

[0161] In a preferred embodiment, the power pads can be configured as a whole block or a grid (such as a 2×2 4-grid pad), as shown in FIG3C and FIG3D . In FIG3C , the power pads are in a mixed form of a whole block and a grid, and in FIG3D , all the power pads are grid-shaped pads.

[0162] The pads through which energy flows into and out of the half-bridge power module are collectively referred to as power pads, including the half-bridge positive pad, the half-bridge negative pad and the half-bridge midpoint pad (in some embodiments, the half-bridge midpoint may not participate in the circuit connection so that a corresponding pad is not required or the corresponding pad is left floating). Each grid-shaped power pad includes several sub-pads, which are short-circuited together inside the packaging structure through a good electrical conductor; from another perspective, the sub-pads short-circuited together inside the module through a good electrical conductor are also regarded as belonging to the same power pad; the pads through which signals flow into and out of the half-bridge module are collectively referred to as signal loop pads. Similarly, each grid-shaped signal loop pad includes several sub-pads, which are connected together inside the packaging structure through a good electrical conductor; since the signal loop pads corresponding to the same signal inflow and outflow ends are generally arranged adjacent to each other, the signal loop pads are usually arranged in pairs or groups.

[0163] For a pad layout design that meets the safety insulation spacing requirements, on the pad surface, the maximum area allowed for the same power pad to be set or the maximum area allowed for its sub-pad to be set (for grid-shaped pads) is called the power pad area. The maximum area that can be used to place the same pair or group of signal loop pads is called the signal pad area. Power pads or pairs / groups of signal loop pads can be arranged in any shape and any number of pads or sub-pads within their corresponding pad areas. In some embodiments, NC pads are also provided on the pad surface, and the area where the NC pads are set can also be regarded as one or more signal pad areas.

[0164] Since a half-bridge power module requires at least one pair / group of signal return pads and at least two power pads, the pad surface is typically provided with at least one signal pad area and at least two power pad areas. In a preferred embodiment, as shown in FIG3G , three power pads (referred to as first to third power pads, respectively) and three pairs / groups of signal return pads (referred to as first to third signal return pads, respectively). The length and width of the pad surface are L1 and W1, respectively. The insulation spacing between the first power pad and the first signal loop pad is no less than D1, the insulation spacing between the second power pad and the second signal loop pad is no less than D2, the insulation spacing between the third power pad and the third signal loop pad is no less than D1, the insulation spacing between the first power pad and the second power pad is no less than D3, and the insulation spacing between the second power pad and the third power pad is no less than D4. Each signal pad area 110 is set to the same width D5. The insulation spacing between the first signal loop pad and the second signal loop pad is no less than D6, and the insulation spacing between the second signal loop pad and the third signal loop pad is no less than D7. The length and width of the first and third power pad areas 111 / 113 corresponding to the first and third power pads are set to be the same. In order to make the area of ​​the second power pad area 112 the same as the areas of the first and third power pad areas, the length and width of each power pad area can be calculated according to the following formula.

[0165] The length L2 and width W2 of the first and third power pad regions can be selected as follows: L2 = W1-D1-D5 (1) W2 = (L1-D3-D4)×(W1-D2-D5) / (3×W1-D1-2×D2-3×D5) (2)

[0166] The length L3 and width W3 of the second power pad area can be selected as follows: L3 = W1-D2-D5 (3) W3 = L1-D3-D4-2×W2 (4)

[0167] The sum L4 of the lengths of the signal pad regions 110 is: L4 = L1 - D6 - D7 (5)

[0168] FIG3H and FIG3I are two preferred embodiments designed according to this principle, in which each pin pad 11 is a grid-shaped pad. Each pad area is provided with sub-pads (including mandatory pads 11a and selective pads 11b) arranged in an array. In order to reduce the difficulty of designing the printed circuit board routing for the user, the user only needs to solder the mandatory pads 11a corresponding to the hatched pattern in the figure, and the selective pads 11b corresponding to the hollow pattern can be selectively soldered. The selection basis of the mandatory pads 11a and the selective pads 11b is as follows: the sub-pads located in the corners of the pad area are mandatory pads 11a, and the sub-pads adjacent to the sub-pads in the corners (excluding diagonally adjacent) are also mandatory pads 11a, and each selective pad 11b is adjacent to at least two mandatory pads 11a (including diagonally adjacent).

[0169] In a preferred embodiment, as shown in FIG3J , a Sink pad electrically connected to the heat dissipation surface of the module is also provided on the pad surface. The distance between the Sink pad and other surrounding pin pads 11 meets the safety requirements. When using this module, the user can choose to electrically connect the Sink pad to the power pad corresponding to the DC-end or other electrostatic potential terminals to reduce the common mode current.

[0170] In a preferred embodiment, in order to facilitate parallel connection of the half-bridge modules, the four edges of the pad surface are defined as the first to fourth edges in sequence, and each power pad area is arranged in sequence along the second and fourth edges of the pad surface, and the second edge and the fourth edge are defined as parallel adjacent edges, and each power pad area is adjacent to each parallel adjacent edge. The same power pad area can be a continuous whole block or multiple discrete blocks. As shown in Figures 4A, 4B, 4D, and 4E, each power pad area is a whole block, while Figure 4C shows an embodiment in which some power pad areas are multiple blocks. Each power pad can be provided with pads or sub-pads of any shape and any number within its corresponding power pad area. Figures 4G, 4H, 4I, and 4J show examples in which a pad area has only one pad.

[0171] In a preferred embodiment, as shown in FIG4A , a first power pad is arranged in a first power pad area 111, a second power pad is arranged in a second power pad area 112, and a third power pad is arranged in a third power pad area 113. The pad surface is divided into 3×3 pad surface sub-areas a to i. Two signal pad areas 110 share corresponding pad surface sub-areas b and h with the first power pad area 111 and the third power pad area 113, respectively, including a first signal pad area and a second signal pad area. A pair of first signal loop pads is arranged in the first signal pad area, and a pair of second signal loop pads is arranged in the second signal pad area. The insulation spacing between the first power pad area 111 and the third power pad area 113 and the signal pad area 110 is no less than D1, the insulation spacing between the first power pad area 111 and the second power pad area 112 is no less than D3, and the insulation spacing between the second power pad area and the third power pad area is no less than D4. The first to third power pad areas 111 / 112 / 113 are arranged in a centrally symmetrical layout, and the two signal pad areas 110 are respectively located outside the corresponding first and third power pad areas 111 / 113 (ie, the power pad areas surround the signal pad area 110 on three sides facing outward).

[0172] In another preferred embodiment, as shown in FIG. 4B , the difference from FIG. 4A is that two signal pad areas 110 are located inside the corresponding first and third power pad areas 111 / 113 (ie, the power pad areas surround the signal pad area 110 on three sides facing inward).

[0173] In another preferred embodiment, as shown in FIG4C , the difference is that the first power pad area is split into two symmetrical pad areas 111A and 111B, the third power pad area is split into two symmetrical pad areas 113A and 113B, and a signal pad area 110 is respectively provided between the pad area 111A and the pad area 111B, and between the pad area 113A and the pad area 113B.

[0174] In another preferred embodiment, as shown in FIG4D , the difference is that the first power pad area 111 surrounds the signal pad area 110 on three sides facing inward, and the third power pad area 113 surrounds the signal pad area 110 on three sides facing outward. In other embodiments, the first power pad area 111 can be replaced with the first power pad area 111 surrounding the signal pad area 110 on three sides facing outward, and the third power pad area 113 surrounding the signal pad area 110 on three sides facing inward (not shown).

[0175] In another preferred embodiment, as shown in FIG4E , the difference is that one signal pad area 110 shares the sub-areas g-i on the pad surface near the third edge with the third power pad area 113, that is, the signal pad area 110 is completely disposed outside the third power pad area 113. The other signal pad area 110 can be arranged in the same manner as in the previous embodiment, or can refer to the same layout method of being completely located outside.

[0176] Figure 4F shows a circuit diagram of a standard half-bridge topology with temperature monitoring. The half-bridge positive terminal pad, half-bridge negative terminal pad, and half-bridge midpoint terminal pad correspond to the DC+, DC-, and SW terminals in the circuit diagram, respectively. A pair of signal loop pads correspond to the control signal terminals of the upper bridge arm switch, namely the GH and SH terminals. The other three signal loop pads correspond to the control signal terminals of the lower bridge arm switch, namely the GL and SL terminals, and the temperature signal output terminal, namely the SENSE terminal. (Since the temperature monitoring and control signals share the SL terminal, the signal loop pads corresponding to these three signal terminals form a group.) In subsequent Figures 4G to 4O, each pin pad is labeled according to its circuit function. Figure 4G is a specific embodiment of Figure 4A. The first power pad area 111 corresponds to the SW terminal, with the GH and GL terminals adjacent to the SW terminal on the pad surface. The second power pad area 112 corresponds to the DC+ terminal, and the third power pad area 113 corresponds to the DC- terminal. The GL, SL, and SENSE terminals are adjacent to the DC- terminal on the pad surface.

[0177] FIG. 4H is a specific embodiment of FIG. 4B .

[0178] FIG4I is a specific embodiment of FIG4C .

[0179] FIG4J is a specific embodiment of FIG4D .

[0180] The power pad areas in FIG4G , FIG4H , FIG4I , and FIG4J are all covered by a whole pad. In some other embodiments, they may also be arranged in a grid shape, that is, a plurality of small square sub-pad arrays fill the pad area, as shown in FIG4K .

[0181] In a preferred embodiment, the impedance between any two sub-pads corresponding to the same pin pad 11 is no more than 3 mΩ, so it is not necessary to solder all the sub-pads during use. As shown in FIG4L , only a portion of the sub-pads corresponding to the shaded pattern in the figure can be soldered.

[0182] When multiple half-bridge modules are used in parallel, decoupling capacitors 19 can be placed between the half-bridge modules to reduce switching noise. As shown in Figures 4M, 4N, and 4O, each power pad is adjacent to two adjacent parallel edges (i.e., the second and fourth edges) at the same time, so that the parallel electrical connection traces outside the module can be set to the shortest. The power pad corresponding to the SW end is set near the first edge of the pad surface, and the power pads corresponding to the DC+ and DC- ends are set in the middle of the pad surface and near the third edge, which can facilitate the electrical connection of the decoupling capacitors 19. In some other embodiments, the decoupling capacitors can also be integrated into the module, so that when the modules are used in parallel, there is no need to place capacitors between the modules.

[0183] In a preferred embodiment, each power pad area and one signal pad area in Figures 4A, 4B, 4D, and 4E are split into two, resulting in six power pad areas 111A-113B and three signal pad areas 110. As shown in Figure 4P, the pad surface is divided into 4×3 pad surface sub-areas a-l. Pad areas 111A-113B are each located in two adjacent pad surface sub-areas, and the three signal pad areas 110 are located in pad surface sub-areas b, c, and j-k, respectively. This approach allows the pad surface design to be compatible with full-bridge modules. In a half-bridge module, pad areas 111A / B share the same power pad, pad areas 112A / B share the same power pad, and pad areas 113A / B share the same power pad. The two signal pad areas 110 near the first edge share the same pair / group of signal return pads, and the signal pad area 110 near the third edge shares the same pair / group of signal return pads. If it is a full-bridge module, taking the circuit shown in Figure 4R as an example, that is, a packaging structure in which two half-bridge circuits electrically connected at one end are packaged together, the pad area 111A corresponds to the SW1 end, the pad area 111B corresponds to the SW2 end, the pad area 112A / B corresponds to the DC+ end, the pad area 113A corresponds to the DC-1 end, and the pad area 113B corresponds to the DC-2 end. The GH1 end and the SH1 end are arranged in the signal pad area 110 adjacent to the pad area 111A, and the GH2 end and the SH2 end are arranged in the signal pad area 110 adjacent to the pad area 111B. The remaining signal loop pads (corresponding to the GL1 end, SL1 end, GL2 end, SL2 end, T1 end, and T2 end) are arranged in the signal pad area 110 adjacent to the pad area 113A / B, as shown in Figure 4U. Taking the circuit shown in Figure 4S as an example, that is, a packaging structure in which two half-bridge circuits are directly packaged together, pad area 111A corresponds to the SW1 end, pad area 111B corresponds to the SW2 end, pad area 112A corresponds to the DC+1 end, pad area 112B corresponds to the DC+2 end, pad area 113A corresponds to the DC-1 end, pad area 113B corresponds to the DC-2 end, GH1 end and SH1 end are arranged in the signal pad area 110 adjacent to pad area 111A, GH2 end and SH2 end are arranged in the signal pad area 110 adjacent to pad area 111B, and the remaining signal loop pads are arranged in the signal pad area 110 adjacent to pad area 113A / B, as shown in Figure 4V. Taking the circuit shown in Figure 4T as an example, that is, a packaging structure in which two half-bridge circuits in parallel are packaged together, the pad area 111A corresponds to the SW1 end, the pad area 111B corresponds to the SW2 end, the pad area 112A / B corresponds to the DC+ end, the pad area 113A / B corresponds to the DC- end, the GH1 end and the SH1 end are arranged in the signal pad area 110 adjacent to the pad area 111A, the GH2 end and the SH2 end are arranged in the signal pad area 110 adjacent to the pad area 111B, and the remaining signal loop pads are arranged in the signal pad area 110 adjacent to the pad area 113A / B, as shown in Figure 4W.

[0184] In another preferred embodiment, the signal pad area near the third edge is also divided into two, that is, there are four signal pad areas 110 in total.

[0185] The signal pad area 110 can be set at any corner of the power pad area adjacent to it, surrounded by the power pad area on two sides, or it can be set on any edge of the power pad area adjacent to it, surrounded by the power pad area on three sides. The four signal pad areas 110 can each be independently set in relative position, and share the pad surface sub-areas a and / or b, c and / or d, i and / or j, k and / or l with the pad areas 111A, 111B, 113A, and 113B respectively. Figure 4Q is an example in which three signal pad areas 110 are set at the corners of the power pad area, and one signal pad area 110 is set on the edge of the power pad area adjacent to the third edge. Taking the circuit shown in Figure 4R of the full-bridge module as an example, the pin definition corresponding to the circuit function is shown in Figure 4X. The examples of the circuits shown in Figures 4S and 4T are similar and will not be repeated.

[0186] Since the PCB and DBC board in the half-bridge power module of this embodiment can form a more flexible electrical connection route through 3D packaging, the number of circuit layers of the PCB can also be flexibly set according to needs, which can be a double-sided board or a four-sided board or even more, so as to more flexibly allocate the connection path from the bottom pin to the pad.

[0187] Example 2

[0188] This embodiment differs from the first embodiment in that, in applications such as automotive scale assembly, the solder joint quality needs to be observed after soldering, so the SMD pads need to partially extend to the side of the module. The PCB of this embodiment can be provided with a hemming edge, meaning that at least one SMD pad extends to the side of the module, as shown in Figure 5A. This allows the solder to wet the bottom pad and then climb to the side. Observing solder on the side indicates good wetting and solder quality.

[0189] Since the side of the half-bridge power module of this embodiment is an insulating surface for insulation and creepage, the side extension 18 of the pad cannot occupy too much height, which will affect the creepage distance of the module. In a preferred embodiment, the side extension 18 is set by setting a depth-limiting hole on the motherboard of the PCB. For example, a hole with a diameter of 0.5mm and a depth of 0.5mm is set on a 1mm thick PCB. In this way, when the PCB is plastic-sealed, the PCB is still sealed and the plastic sealing is not affected. Then, when the board is separated, the depth-limiting hole is cut open, leaving a part of the side wall to form the required side extension of the pad. Another way to set the side extension is to set a through hole on the motherboard of the PCB and then fill the hole. In this way, the PCB is also sealed, and the subsequent steps are the same as the previous setting method.

[0190] On the other hand, since the packaging filler (such as plastic compound) has to flow through between the DBC and the PCB during the process, the mold flow pressure is very high, which can be as high as 100 atmospheres. When the mold flow flows through, it generates an impact between the DBC and the PCB, forming an external tearing force, causing the solder joints connecting the two to be torn.

[0191] In this embodiment, a number of fixing columns 161 are provided between the DBC and the PCB. The ends of the fixing columns 161 are strongly connected to the PCB and DBC structures, holding both together during injection molding to prevent tearing of the solder joints. This embodiment has requirements for the distribution position and density of the fixing columns 161. In the horizontal direction, at least one fixing column 161 is provided in each of the module parts corresponding to the left front, left rear, right front, and right rear quadrants of the DBC. The fixing columns 161 can be formed using structural members with a certain strength, such as copper columns. The total soldering area of ​​the fixing columns 161 is not less than 2% of the area of ​​the DBC, and preferably not less than 5%, to ensure sufficient pulling force to resist the impact of mold flow. In some embodiments, they can also serve as electrical connections, that is, they are provided as the electrical connection columns 16 in the first embodiment. As shown in FIG5B , when fixing post 161 is soldered together with other electronic components, to ensure precise soldering of the other components, the height Hpole of fixing post 161 should be smaller than the height of the other components (e.g., the sum of the thicknesses of the power chip and its front electrodes, Hdie). The difference between the two should be at least 20 μm, preferably 50 μm. This allows for more solder to be placed on the fixing post to absorb tolerances, allowing for a thinner steel mesh for soldering and achieving precise soldering of the power chip and other components. The soldering of fixing post 161 can be achieved by increasing the opening area of ​​the steel mesh to provide sufficient solder volume, for example, to at least 120%, preferably at least 150%, of the soldering area of ​​the top of fixing post 161. Furthermore, to ensure that the encapsulation filler completely fills the gaps between the electrodes and maintains the structural safety of the power chip, if the front of the power chip is directly soldered to the PCB using conductive balls (i.e., in the case where electrical connection post 17 is a conductive ball in the first embodiment), the diameter of the conductive ball should be set to at least 0.2 mm, preferably at least 0.3 mm. It should be noted that, in this embodiment, the power chip has a back side facing the electrically insulating heat conducting plate, and a front side facing the PCB.

[0192] In another preferred embodiment, the impact of mold flow pressure can also be offset by improving the manufacturing process. As shown in Figure 5C, during the package filling process, a channel with a thickness Hm of at least 0.3mm (preferably at least 0.5mm) is left under the heat dissipation surface of the module for mold flow, that is, Hm ≥ 0.3mm, especially Hm ≥ 0.5mm is preferred. In this way, the mold flow simultaneously generates equal pressure on the upper and lower surfaces of the DBC, offsetting each other, reducing the external tearing force between the DBC and the PCB and leaving an overflow area 131 on the heat dissipation surface. Obviously, the overflow area 131 needs to be removed by grinding after the package filling; in addition, in some precision scenarios, the heat dissipation surface of the DBC needs to be ground after the module is plastic-sealed to ensure that the flatness of the heat dissipation surface is better than 100μm while also having the opportunity to achieve a total module thickness tolerance of less than 50μm. In this way, there is a requirement for the thickness of the copper clad surface on the back of the DBC, that is, the copper clad surface on the back of the DBC is further thickened compared to the copper clad area on the front. To ensure smooth grinding, the thickness of the copper clad surface on the back of the DBC is not less than 150μm, preferably not less than 250μm. At the same time, to ensure the etching accuracy of the DBC copper clad area, its thickness is set to be smaller, such as 50μm or even 100μm thinner than the copper clad surface on the back.

[0193] Example 3

[0194] One difference between this embodiment and the first embodiment is that a concave or convex structure is provided on the side of the plastic package 13. On the other hand, this embodiment also includes a temperature signal element and / or a decoupling capacitor 19 and / or a gate driver chip, as shown in Figures 6A and 6B. Preferably, the temperature signal element / decoupling capacitor 19 / gate driver chip is placed on the side of the PCB facing the chip to reduce the interconnection between the DBC and the PCB. If the temperature signal element / decoupling capacitor 19 / gate driver IC is taller than other chips, the copper area corresponding to its projection on the DBC can be reduced in thickness by etching or other means, or even removed entirely to avoid space.

[0195] Since the thickness of the half-bridge power module 1 is relatively small, the insulating surface of a simple planar structure may not meet the side creepage distance requirements required by safety regulations. Therefore, grooves can be cut on the side of the plastic package 13 to increase the creepage distance. The groove position can be set continuously around the plastic package 13, or it can be set only in a part of the side wall area close to the outer pad, as shown in Figure 6A; in another preferred embodiment, a convex circle can be set around the plastic package 13 to increase the creepage distance. The convex position can be set continuously around the plastic package 13, or it can be set only in a part of the side wall area close to the outer pad, as shown in Figure 6B.

[0196] In a preferred embodiment, as shown in Figure 6G, increasing the PCB thickness can further increase the lateral creepage distance of the half-bridge power module. Considering that the tracking index of the plastic encapsulation material is higher than that of the PCB material, the PCB can be slotted at the edges (for example, by creating a set-depth groove on the PCB motherboard and separating the panels along the set-depth groove). These grooves can then be filled with plastic encapsulation material during the encapsulation process, thereby increasing the proportion of plastic encapsulation material on the side of the half-bridge module. The vias in the thickened PCB can also be processed using thick copper to improve their temperature resistance and electrical conductivity. Since the CTI constant of a PCB is typically less than 200, while the CTI constant of the plastic encapsulation material can reach 400 or even above 600, the higher the proportion of plastic encapsulation material on the module sidewalls, the stronger the module's pressure resistance. Specifically, the total thickness of the module should be no less than 3 mm, preferably no less than 4 mm; the thickness of the exposed portion of the PCB sidewalls should be no more than 1 mm, preferably no more than 0.5 mm, leaving more thickness for the plastic encapsulation material with a higher CTI constant.

[0197] In a preferred embodiment, as shown in FIG6I , the embodiment of FIG6A / FIG6B and the embodiment of FIG6G can be combined. The protrusion or creepage groove of the side wall is set at the position of the side wall plastic material, so that the increased distance is all plastic material with a larger CTI, so that it can withstand an operating voltage of 800V or even higher. The length of the protrusion extending outward (or the creepage groove extending inward) should be no less than 1mm, which is equivalent to an increase of no less than 2mm in creepage distance. The above-mentioned setting of increasing the creepage distance is generally used in scenarios where the DC voltage upper limit is not less than 800V, and preferably the DC voltage upper limit is not less than 1200V.

[0198] In a preferred embodiment, as shown in FIG6H , a thicker layer of good thermal conductor (collectively referred to as a thick thermal conductive metal layer) is welded on the back of the DBC (i.e., the bottom of the half-bridge power module) by silver sintering 25 or high-temperature soldering, and then plastic-sealed. The plastic sealing body 13 covers the side of the silver sintering 25, which can increase the side creepage distance of the half-bridge module.

[0199] In some other embodiments, the creepage distance may be increased simply by retracting the pads on the front side of the PCB or the copper clad surface on the back side of the DBC.

[0200] In a preferred embodiment, the temperature signal element is active, enabling output of only the highest temperature signal element when multiple temperature signal elements are connected in parallel. As shown in FIG6C , the active temperature signal element comprises a temperature measurement unit 20, a signal processing unit 21, an output enable unit 23, and an output switch 22. The temperature measurement unit 20 can be implemented using materials such as a thermistor, a thermocouple, a photosensitive material, or a PN junction. The signal amplification unit 21, the output enable unit 23, and the output switch 22 are all composed of semiconductor devices. FIG6D illustrates a preferred embodiment using a positive temperature coefficient thermistor as the temperature measurement unit 20 and an N-channel metal oxide transistor as the output switch 22. The signal processing unit 21 utilizes an operational amplifier to amplify the signal, and the output enable unit 23 controls the output switch 22 by comparing the voltage signals across the output switch 22. As shown in FIG6E , multiple temperature signal elements are used in parallel. For the module with the highest temperature signal voltage value, the output enable unit 23 maintains the conduction of the corresponding output switch 22. For the module with the lower temperature signal voltage value, the output enable unit turns off the corresponding output switch 22 by comparing the voltage values, thereby outputting only the temperature signal of the module with the highest temperature.

[0201] In a preferred embodiment, the temperature signal element in the module includes a temperature measuring unit 20, and the temperature measuring unit 20 uses a temperature-sensitive Zener diode with a negative temperature coefficient, as shown in Figure 6F. When there are multiple modules, the user only needs to connect the temperature signal output terminals of each module in parallel and pull them up with a pull-up resistor 24 to know the highest temperature among all modules.

[0202] Example 4

[0203] This embodiment mainly describes the application of a half-bridge power module in an on-board OBC power converter 101. As shown in FIG7A , the on-board OBC (including a single-phase charger and a three-phase charger) mainly includes the above functional blocks and related auxiliary modules such as sampling and protection logic. Usually, due to the differentiation of the entire vehicle architecture, the layout of the vehicle body and core components are different, resulting in different shapes of chargers, and it is impossible to form a set of modular design concepts. Through the half-bridge power module proposed in this embodiment, the minimized design of the core power module (i.e., the on-board OBC power converter 101) can be achieved, thereby solidifying the core power module, and only by adjusting the peripheral interface circuits can the application requirements of different OEMs for the component shape be met.

[0204] 7B and 7C show the circuit diagrams of typical single-phase and three-phase on-board chargers. Replacing the individual bridge arm circuits with discrete components using the half-bridge power module 1 proposed in this embodiment can effectively reduce the footprint of power devices, shorten the loop path, reduce the use of insulating sheets, reduce process complexity, and improve reliability.

[0205] In addition to the vehicle-mounted OBC power converter 101 , the present embodiment may also be applied to realize other non-vehicle-mounted high power density AC-to-DC power converter module applications.

[0206] As shown in Figures 7D to 7F, the on-board OBC power converter 101 includes a substrate 3 and at least two half-bridge power modules 1. The substrate 3 includes a first component area 31, a second component area 32 and a third component area 33 arranged in sequence. The first component area 31 is provided with a capacitor 5 and a controller 4, the second component area 32 is provided with a half-bridge power module 1, the heat dissipation surface of the half-bridge power module is provided with a heat sink 7, the third component area 33 is provided with a magnetic element 6 (also provided with a power factor correction chip PFC, the magnetic element 6 in this embodiment is the magnetic core of the transformer), and the driving component 41 corresponding to the bridge arm switch is provided on the other side of the substrate 3 corresponding to the half-bridge power module.

[0207] Specifically, the half-bridge power module includes an SMD half-bridge power module, a multi-layer PCB substrate 3, associated peripheral circuitry, and a magnetic component 6. The power semiconductor module is SMD-soldered to substrate 3, while the magnetic component 6 is placed horizontally to the side and electrically interconnected to substrate 3. The surface of the magnetic component 6 on the same side as the half-bridge power module can have an electrically insulating thermally conductive cover / pad. In other words, the thermally conductive surface of the magnetic component 6 and the half-bridge power module are on the same side of substrate 3 and are mounted together on the same heat sink 7. Only thermal grease needs to be applied to the surface of the heat sink 7; no additional insulation treatment is required.

[0208] In this embodiment, the converter is an isolated ACDC, the magnetic element 6 can be a transformer and an inductor, and at least one of its input power semiconductor and output power semiconductor uses the SMD power semiconductor module of this embodiment, which can be a half-bridge A, half-bridge B, half-bridge C, half-bridge D, half-bridge E or a combination thereof.

[0209] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules 1 and are placed on the left and right sides of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0210] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules 1 and are placed on the same side of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0211] In a preferred embodiment, the input and output power semiconductors are both half-bridge power modules 1 and are placed on the upper and lower surfaces of the substrate 3 respectively. The half-bridge power modules below the substrate and the lower surface of the magnetic element 6 are installed on the same surface of the heat sink 7, and the upper surface of the half-bridge power modules above the substrate and the upper surface of the magnetic element 6 are pressed together with the upper heat sink to achieve double-sided heat dissipation of the converter module.

[0212] In a preferred embodiment, the transformer winding can be composed of a multi-layer PCB copper layer of the substrate 3, achieving extremely high power density and automated production.

[0213] In a preferred embodiment, the transformer winding may be formed by winding a magnetic core and an independent coil, and electrically interconnected with the substrate 3 by hard wire or welding.

[0214] In some other embodiments, the converter module capacitor, control chip and its peripheral circuits can be placed on one side of the power module, taking into account the distance and routing smoothness, and at the same time separated from the high and low voltage areas of the module to avoid interference; preferably, the converter's drive component 41 and controller 4 can be placed on the back of the power module, connected to the power module by the minimum path.

[0215] In some other embodiments, the magnetic components can be independently arranged through the cavity to provide a certain shielding effect, and the upper and lower surfaces are in close contact with the housing or the heat dissipation surface to ensure heat dissipation.

[0216] Example 5

[0217] This embodiment mainly describes the application of a half-bridge power module in a DC-DC isolation converter. As shown in Figures 8A to 8C, the DC-DC isolation converter includes a substrate 3, a transformer core (i.e., a magnetic element 6), and at least one half-bridge power module 1. The half-bridge power module 1 is disposed on the substrate 3. The transformer core and the assembly of the half-bridge power module and the substrate are arranged in parallel, or the transformer core and the half-bridge power module are arranged in parallel on the substrate. The half-bridge power module and the transformer core share a heat sink 7, and an insulating heat conductor 71 is provided between the transformer core and the heat sink.

[0218] Specifically, the half-bridge power module includes an SMD half-bridge power module, a multi-layer PCB substrate 3 and its related peripheral circuits, and a magnetic component 6 .

[0219] The power semiconductor module SMD is soldered on the substrate 3 , and the magnetic element 6 is placed horizontally on the side and electrically interconnected to the substrate 3 . The heat conducting surface of the magnetic element 6 and the half-bridge power module are on the same surface of the substrate 3 and are mounted together on the same heat sink 7 .

[0220] In this embodiment, the converter is an isolated DC-DC converter, the magnetic element 6 may be a transformer, and at least one of the input power semiconductor and the output power semiconductor thereof uses the SMD power semiconductor module of the present invention.

[0221] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules and are placed on the left and right sides of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0222] In a preferred embodiment, both the input and output power semiconductors are half-bridge power modules and are placed on the same side of the transformer core to achieve uniform heat distribution and output power pins on the left and right sides of the converter module.

[0223] In a preferred embodiment, the input and output power semiconductors are both half-bridge power modules and are placed on the upper and lower surfaces of the substrate 3 respectively. The heat dissipation surfaces of each half-bridge power module are on the same side as the magnetic element 6 and are installed on the same heat sink surface to achieve double-sided heat dissipation of the converter module.

[0224] In a preferred embodiment, the transformer winding is composed of a multi-layer PCB copper layer of the substrate 3, achieving extremely high power density and automated production.

[0225] In some other embodiments, an electrically insulating thermally conductive cover / pad (i.e., an insulating thermally conductive member 71) is provided on the surface on the same side of the magnetic element 6 and the half-bridge power module. The electrically insulating thermally conductive cover / pad is made of a deformable buffer material to absorb the displacement tolerance between the heat dissipation surface of the magnetic element 6 and the heat dissipation surface of the half-bridge power module, thereby ensuring a good connection between the half-bridge power module as a high heat density component and the heat sink.

[0226] The module structure of this embodiment has the following advantages:

[0227] 1) Semiconductors with the highest heat density require excellent heat dissipation channels;

[0228] 2) This embodiment has a built-in multi-layer PCB, which can reduce the number of layers required for the substrate 3 PCB. Combined with the SMD application method, the module can be placed directly on the overlapping area above the windings of the magnetic components of the PCB, with almost no increase in the number of layers of the substrate 3;

[0229] 3) The internal laminated structure fully utilizes the PCB component height space created by the thickness of the magnetic core 6.

[0230] In some other embodiments, as shown in Figures 9A to 9B, the difference between Figure 9A and Figure 9B is that the packaging structure of the half-bridge power module 1 is different, and the DCDC isolation converter also includes a secondary insulation treatment structure, which is a secondary plastic package 8 or a glue filling structure. The secondary insulation treatment structure can also be applied to occasions where secondary insulation treatment is required in other embodiments of the present invention.

[0231] Since the thickness of the half-bridge power module 1 can be very thin, such as 3 to 5 mm, and the built-in DBC makes it have the ability to resist safety insulation. However, the creepage distance from the electrode to the heat sink through the side is basically determined by the thickness of the module, making it difficult to directly adapt to scenarios with excessively high safety insulation, such as scenarios as high as 12 to 18 mm. The system applications and related products mentioned in the present invention can also be secondary packaged, so that the creepage distance between the module electrodes and the heat dissipation surface is formed by solid insulation of the packaging filler. Mainly: at least one half-bridge power module 1 is SMD-ed together with at least one other component on a system PCB board to form a PCBA. All components on one side of the PCB where the half-bridge power module 1 is installed are completely immersed in the secondary packaging material together with the PCB surface to achieve solid insulation.

[0232] In some other embodiments, the secondary packaging can be plastic packaging, which can further enhance strength and reliability. Preferably, polishing is performed after plastic packaging to ensure the flatness of the heat dissipation surface of each module and to ensure that multiple modules are in thermal contact with the radiator at the same time.

[0233] In some other embodiments, as shown in FIG9C , the glue filling structure is an insulating glue 9 such as silicone or epoxy glue, and is constrained by a shell 91 on the outside. The shell 91 can directly dissipate heat to the outside, or other radiators 7 can be further installed.

[0234] In a preferred embodiment, the housing is preformed and then placed into the PCBA and then glue-filled.

[0235] In a preferred embodiment, as shown in FIG9D , the housing 91 includes an annular retaining wall 92 and a sealing adhesive 93 . The glue filling structure is configured such that the PCBA is first thermally bonded to the heat sink 7 , and after the annular retaining wall 92 is electrically insulated, the annular retaining wall 92 is bonded to the heat sink 7 via the sealing adhesive 93 , and then the insulating glue 9 is filled.

[0236] In a preferred embodiment, the PCBA has power pins for external connection, and at least a portion of the power pins is directly or indirectly led out of the sealed housing.

[0237] In a preferred embodiment, the PCBA is further stacked with another PCBA and electrically interconnected to add more functions.

[0238] In a preferred embodiment, the upper surface of the chip inside the half-bridge power module 1 is directly electrically welded to the PCB inside the module, thereby realizing an ultra-thin half-bridge power module with a thickness of less than 4 mm.

[0239] Example 6

[0240] This embodiment mainly describes the application of a half-bridge power module in a non-isolated power converter. As shown in FIG9E , the non-isolated power converter includes a substrate 3, a magnetic element 6 and at least one half-bridge power module 1; the half-bridge power module 1 is arranged on the substrate 3; the magnetic element 6 is arranged in parallel with the assembly of the half-bridge power module 1 and the substrate 3, or the magnetic element 6 is arranged in parallel with the half-bridge power module 1 on the substrate 3; the half-bridge power module 1 and the magnetic element 6 share a heat sink 7, and an insulating heat conductor 71 is arranged between the magnetic element 6 and the heat sink 7.

[0241] Specifically: a power module of the non-isolated power converter includes an SMD half-bridge power module 1, a multi-layer PCB substrate 3 and its related peripheral circuits, and a magnetic component 6. The half-bridge power module is soldered on the substrate 3 through SMD, and the magnetic component 6 is placed horizontally on the side and electrically interconnected to the substrate 3. The surface of the magnetic component 6 on the same side as the half-bridge power module 1 can have an electrically insulating thermal conductive cover / pad (i.e., an insulating thermal conductive part 71), so that the thermal conductive surface of the magnetic component 6 and the half-bridge power module 1 are on the same surface of the substrate 3 and are almost flush, so that they can be installed together on the same heat sink 7.

[0242] In this embodiment, the non-isolated power converter can also be a DCDC or ACDC or DCAC, and its power semiconductor uses at least one power module of this embodiment. The lower surface of the PCB is a half-bridge power module 1, and the upper surface is small components such as ceramic capacitors 42 to form a PCBA. In this embodiment, the magnetic element 6 is illustrated using an inductor element as an example.

[0243] In a preferred embodiment, the inductor component is a copper-iron preformed component, which is placed on the side of the PCBA and electrically connected.

[0244] In a preferred embodiment, as shown in FIG9F , the inductor element is a copper-iron preformed element having a thickness comparable to that of the half-bridge power module 1 and is soldered together with the half-bridge power module on the same side of the PCB.

[0245] In a preferred embodiment, as shown in Figure 9G, the winding or part of the winding of the inductor element is a wiring layer of the PCB. The inductor magnetic material has a part on each of the upper and lower surfaces of the PCB.

[0246] Example 7

[0247] This embodiment mainly describes the application of a half-bridge power module in a cardiac arrest awakening device 102. As shown in Figures 10A and 10B, the cardiac arrest awakening device 102 includes a shell 91, a first PCBA component layer, a second PCBA component layer and an insulating glue 9. The first PCBA component layer and the second PCBA component layer are stacked in the shell, and the filling glue is filled in the gap between the shell, the first PCBA component layer and the second PCBA component layer; the first PCBA component layer includes a power supply element 102a and a power drive element 102b, and the second PCBA component layer includes at least one half-bridge power module. The at least one half-bridge power module is used to generate a high-voltage pulse output, and the heat dissipation surface of the half-bridge power module is in contact with the shell; the cardiac arrest awakening device 102 also includes a magnetic element 6 (specifically an inductor) and a release resistor 102c. The magnetic element 6 and the release resistor 102c can be set on the first PCBA component layer or the second PCBA component layer as needed.

[0248] Specifically, the cardiac arrest awakening device includes at least one half-bridge power module (with a built-in high-voltage switching bridge arm for converting high-voltage DC into high-voltage pulses) placed on one side of a PCB. The driver for the half-bridge power module is located on the other side of the PCB, forming a main PCBA. The main PCBA is equipped with power pins for external electrical connections. The PCBA is placed in a housing and filled with silicone or epoxy adhesive, submerging almost the entire PCBA to achieve high-voltage insulation.

[0249] In some other embodiments, a secondary PCBA is stacked with the main PCBA and electrically connected to the main PCBA, and both are submerged in the colloid to achieve more functions.

[0250] Preferably, the secondary PCBA may be provided with a high-voltage isolation power supply low-voltage input low-voltage output DCDC converter required by the half-bridge power module driver, and the two PCBAs may be connected through internal pins for power supply.

[0251] In a preferred embodiment, the secondary PCBA may also be provided with a low-voltage-input and high-voltage-output DCDC converter, which converts the external low-voltage DC power supply into high-voltage DC and then provides it to the bridge arm placed in the half-bridge power module to convert it into a high-voltage pulse, and then provides it to the external connection through the power pin or even stimulates the human heart to wake up.

[0252] In a preferred embodiment, the main and auxiliary PCBAs are provided with choke inductors connecting the high voltage DC and the bridge arms.

[0253] In some other embodiments, the housing 91 is a good thermal conductor, such as a metal shell.

[0254] In a preferred embodiment, a release resistor for releasing the energy of a capacitor storing high-voltage DC energy when not needed is in thermal contact with the housing, thereby expanding the heat dissipation capacity of the release resistor and reducing its volume.

[0255] In a preferred embodiment, the metal shell is connected to the GND of the external low-voltage input to achieve overall shielding.

[0256] In other embodiments, because pulse voltages can reach thousands of volts, common-mode noise can easily interfere with complex wake-up calculations. The metal layer on the heat sink surface of the half-bridge power module can be electrically connected to a static ground potential, such as a relatively stable potential relative to the battery GND, to provide common-mode shielding and reduce common-mode interference.

[0257] In other embodiments, due to the discontinuous nature of cardiac pacing, the half-bridge power module relies solely on the thermal capacity of its structural material system for thermal management. To reduce the risk of unnecessary short circuits, the heat dissipation surface of the module can be covered with at least 0.4mm of plastic material.

[0258] The dimensions of the high-voltage generating core component of the cardiac pacemaker in this embodiment have been significantly reduced from the original 12cm x 6cm x 2.4cm to 6cm x 5mm x 2cm. This significantly reduces the size of the entire wake-up device, making it more likely that patients will carry it with them, saving more lives and having significant implications.

[0259] Example 8

[0260] This embodiment primarily illustrates the application of a half-bridge power module in a large IPM module. Specifically, multiple small half-bridge power module units are SMD-soldered to the same surface of a multi-layer PCB converter board 11, resulting in a nearly flat heat dissipation surface, as shown in Figures 11A and 11B. The other side of the PCB provides flexible placement for large module pins, drivers, capacitors, inductors, conductive screw holes, fixing screw holes, and more. Gold finger pins can even be placed on the upper and lower edges of the PCB to reduce cost and size. Copper busbars and other power connectors can also be embedded. Furthermore, a secondary adhesive filling process (as indicated by the insulating adhesive 9 in Figure 11A) can be performed on the module-side PCB, significantly increasing creepage distance.

[0261] The internal contents of each module can be exactly the same, for example, two half-bridge sub-modules form a full bridge, and three half-bridge sub-modules form a three-phase bridge.

[0262] Modules with different contents can also be combined to form more types of circuit units: for example, a high-voltage half-bridge module plus a dual-transistor back-to-back series module (the back-to-back series bridge arm circuit is considered a special case of a half-bridge circuit in this invention) forms a TNPC circuit unit. For example, two IGBT half-bridge modules plus a SiC half-bridge module form an ANPC circuit unit.

[0263] The components of the above modules can also be connected in parallel to form a larger half-bridge power composite module. Multiple circuit units can also be connected in parallel to form a higher-power high-voltage electronic switch.

[0264] In some scenarios with particularly high heat density, especially those with relatively high transient power, extreme heat dissipation capabilities are required. Therefore, it is recommended that the heat dissipation surfaces of each module subunit in this embodiment be hard-bonded to the heat sink using a material with excellent thermal conductivity, as shown in FIG11B . For example, this could be achieved using a metal sintering process, such as silver sintering 25 . However, if the module is still SMD-mounted to a PCB converter board, the upper and lower surfaces of the module are hard-connected, which in some cases lacks stress buffering and can lead to reliability risks. Therefore, the module can be prefabricated with pins with strong buffering capabilities before being soldered to the converter board.

[0265] In a preferred embodiment, as shown in FIG11C , at least two half-bridge power modules 1 are welded on a substrate 3, and a decoupling capacitor 19 is placed next to the half-bridge power module 1 to reduce the area of ​​the electrical loop between the decoupling capacitor 19 and the half-bridge power module 1. A thin film capacitor 26 (i.e., a Vbus capacitor) is placed near the decoupling capacitor 19 to reduce the area of ​​the electrical loop between the decoupling capacitor 19 and the thin film capacitor 26. An insulating heat conductor 71 with high thermal conductivity is provided between the decoupling capacitor 19 and the heat sink 7 to prevent the decoupling capacitor 19 from overheating. The PCB conversion board 27 where the control and drive are located is pressed onto the substrate 3 through elastic pins 28 to provide stress buffering, thereby achieving low-loop, low-assembly challenge, high-reliability interconnection, and flexible matching of the drive. The edge of the substrate 3 is connected to the outside world using gold finger pins or embedded copper bars.

[0266] Packaging multiple modules and capacitors into an integral module will pose a challenge to leakage current testing. During the test, the sum of the leakage current and the capacitor charging current may be measured. To solve this problem, the capacitor can be connected in parallel to the leakage current test circuit before testing the leakage current. Taking Figure 11D as an example, one pin of the decoupling capacitor 19 is electrically connected to the suspended pad 29. After the leakage current test is passed, the suspended pad 29 and the pad corresponding to DC+ are welded. Figure 11D corresponds to the case where the decoupling capacitor 19 is set on the back of the substrate 3. The pin of the decoupling capacitor 19 can be directly welded to the suspended pad 29; and for the case where the decoupling capacitor 19 is set adjacent to the half-bridge power module 1, one pin of the decoupling capacitor 19 can also be electrically connected to the suspended pad 29 through a via or the like.

[0267] Figure 11E shows the manufacturing process of packaging multiple modules, capacitors, and liquid-cooled radiators together. First, the half-bridge power module 1 and the annular retaining wall 92 are fixed to the radiator 7 (the half-bridge power module 1 can be fixed by welding or with glue with high thermal conductivity, and the annular retaining wall 92 is fixed with glue). Then, the substrate 3 is welded, and then the decoupling capacitor 19 is welded (for the case where the decoupling capacitor 19 is set adjacent to the half-bridge power module 1, the corresponding steps are adjusted according to the corresponding description in Figure 11C) and the elastic pin 28. In this step, the leakage current can be measured according to the aforementioned method before the decoupling capacitor 19 is fully connected to the circuit. After welding, the cover plate 94 is installed to seal it into a whole. Plastic sealing can be selected. Finally, the heat dissipation liquid pipeline corresponding to the radiator 7 is installed.

[0268] Example 9

[0269] This embodiment mainly describes the related applications of half-bridge power modules to form more complex circuit structures; as shown in Figure 12A, since the half-bridge power module needs to be used in multiple combinations, its pins must take into account the convenience of application combination use, so the pads with different functions need to be set in rows. Take m as an example to illustrate, that is, 4 rows of pad surface area, the corresponding pad functions from the first row to the fourth row are: signal (drive), DC-, DC+, SW, because switches with the same function may be composed of multiple components in parallel, so the number of pad columns can be set accordingly according to the number of components in parallel.

[0270] In a preferred embodiment, as shown in Figures 12B and 12C, three half-bridge power modules 1 form a three-phase bridge circuit, and the DC+ pads and DC- pads of the three half-bridge power modules 1 are electrically connected to the same DC+ terminal and the same DC- terminal, respectively, and the u terminal, v terminal, and w terminal are respectively led out (corresponding to the midpoint terminals of the bridge arms of the three half-bridge power modules 1, respectively), that is, each dotted box area in the figure is electrically connected to the same terminal.

[0271] In a preferred embodiment, as shown in FIG12D and FIG12E , three half-bridge power modules 1 are arranged in parallel to form a power expansion, and the u-end, v-end, and w-end can be further electrically connected to the same SW1 end based on the three-phase bridge circuit structure.

[0272] In a preferred embodiment, as shown in Figures 12F and 12G , the framed areas of the same shading in Figure 12G indicate that the pads within the areas are electrically connected to the same end. The ANPC circuit requires two modules: a SiC MOS half-bridge and an IGBT half-bridge, each corresponding to a half-bridge power module 1 (different types of half-bridge modules have different types of bridge arm switches). Two IGBT modules can be placed one above the other to form an IGBT three-level bridge, which can then be joined to the left and right SiC bridges to form a complete ANPC circuit sub-unit (the rounded dashed box in Figure 12G represents an ANPC circuit sub-unit).

[0273] Since the power of the ANPC circuit is relatively large, three half-bridge power modules 1 can form an ANPC circuit sub-unit, and then the ANPC circuit sub-units are arranged in parallel, thus achieving extremely small loop inductance.

[0274] In a preferred embodiment, the TNPC circuit also requires two modules: a half-bridge and a bidirectional switch. The pad layout of the half-bridge power module 1 corresponding to the bidirectional switch is shown in Figure 12H . This half-bridge power module 1 does not require a midpoint lead-out for the bridge arm; the two ends of the bridge arm are labeled SW1 and SW2, respectively. This module is placed side by side with the half-bridge power module to form a TNPC circuit subunit. The circuit diagram and pad electrical connections are shown in Figures 12I and 12J (the rounded dashed box in Figure 12J represents a TNPC circuit subunit).

[0275] Since the power of the TNPC circuit is relatively high, multiple TNPC circuit subunits can be arranged in parallel relative to each other to achieve extremely small loop inductance.

[0276] In a preferred embodiment, as shown in Figures 12K and 12L , the Heric circuit also requires two submodules: a half-bridge and a bidirectional switch. A Heric circuit unit includes two half-bridge power modules 1 corresponding to the half-bridge circuits and one half-bridge power module 1 corresponding to the bidirectional switch. The full bridge can be formed by placing the two half-bridge modules in parallel, which is then combined with the bidirectional switch module.

[0277] In some other embodiments, a solid-state relay circuit may be formed by connecting a plurality of bidirectional switch half-bridge power modules 1 in parallel.

[0278] In the above application, multiple half-bridge power modules 1 are used, and these half-bridge power modules 1 are welded together on a PCB (substrate 3) to achieve the required functions. However, due to the module thickness tolerance and welding thickness tolerance, when multiple half-bridge power modules 1 are pressed onto the same heat sink 7, the gaps on the thermal contact surfaces are inconsistent. Large gaps lead to poor heat dissipation and a risk of overheating. If screw holes are provided near each half-bridge power module 1 to press the substrate 3 and heat sink 7 together, the deformation of the PCB substrate 3 can be effectively utilized to absorb the gap tolerance and ensure the heat dissipation safety of each half-bridge power module 1. However, the pad stress at the corners of the pad surface of each half-bridge power module 1 is relatively high.

[0279] To address this issue, in a preferred embodiment, as shown in FIG12M , each half-bridge power module 1 is provided with at least one pressure pin 95 (which can be in the form of a pin or a block), which is pressed against the back side of the substrate 3 (the front side where the half-bridge power module 1 is soldered). The contact point between the pressure pin 95 and the substrate 3 corresponds to the center of the solder pad surface of the half-bridge power module 1. When the heat sink 7 is fixed via the housing 91, the cover plate 94 applies pressure to the substrate 3 through the pressure pin 95, causing the substrate 3 to deform to absorb the gap tolerance. Preferably, the substrate 3 can be provided with vias corresponding to the gaps between the modules to improve the plasticity of the PCB.

[0280] In another preferred embodiment, as shown in FIG12N , a heat sink 7 that can independently adapt to tolerances is configured for each module. When the housing 91 is installed, the radiator 7 will automatically fit the module through the pressure spring 96, and the heat dissipation liquid channel inside the (liquid-cooled) radiator 7 is connected to the heat dissipation liquid pipeline in the housing 91 through an interface hose 97. When the radiator 7 adapts to the tolerance, the interface hose 97 is deformed accordingly. At this time, the substrate 3 does not need to be deformed, and no ejector pins / ejector blocks need to be configured, so that more space can be used to place components on the substrate 3.

[0281] The switch disclosed in the present invention can be Si MOSFET, SiC MOSFET, GaN MOSFET, IGBT, or Dio, etc., all of which can achieve the functions of the switch disclosed in the present invention.

[0282] Example 10

[0283] This embodiment primarily discloses a multi-layer PCB wiring layer layout for achieving lower bridge arm loop inductance in the packaging structure of a half-bridge power module. As shown in FIG13A , the bridge arm loop inductance is parasitic in the loop formed by the bridge arm (the bridge arm includes an upper bridge arm switch QH and a lower bridge arm switch QL connected in series) and a capacitor C connected across the DC+ and DC- terminals corresponding to the bridge arm. The power chip corresponding to the bridge arm switch is located inside the module; the capacitor C can be located inside or outside the module. In either case, the PCB wiring layer layout is required to minimize the loop area formed by the bridge arm switch itself.

[0284] To achieve this goal, as shown in Figure 13B , the PCB of this embodiment is configured with at least four wiring layers. From left to right in the figure, they are: the first layer (the device layer), the second and third layers (inner layers), and the fourth layer (the pad layer). At least one of these four layers is provided with a large DC-wiring area, and at least one layer is provided with a large DC+ wiring area. These two layers are adjacent, ensuring that the large DC- and DC+ wiring areas overlap by at least 10%, providing a high-frequency current coupling path and reducing loop inductance.

[0285] When the device corresponding to the power chip built into the module is a vertical device, meaning that both the front and back sides of the power chip have power electrodes, electrical connection posts 16 are required to electrically connect the power electrodes from the metal layer on the top surface of the DBC to the device layer of the PCB. Since the back sides of the two power chips are typically not at the same potential, for example, corresponding to the DC+ terminal and the SW terminal, respectively, at least two electrical connection posts 16 are required. These two electrical connection posts 16 are placed side by side and parallel between the two power chips to minimize space waste, resulting in a small module size and reduced current path and loop inductance. SiC is preferably used for this vertical device. In a preferred embodiment, the power chip is a SiC power chip measuring approximately 5mm*5mm, with a withstand voltage of 1200V and an Rdson of less than 15mOhm. Through the structural arrangements disclosed in this embodiment and the previous embodiments, a total size of less than 16*10*4(H)mm can be achieved, making it suitable for half-bridge modules with an operating frequency of no less than 100kHz, preferably no less than 500kHz, and even with a frequency applicability of up to 1MHz. The volume is less than one-third of existing products, and the loop inductance is less than one-fifth of existing products, which can greatly improve the performance of SiC.

[0286] Most wiring layers are divided into at least three wiring areas, which are arranged in sequence up and down, with DC+ between SW and DC- (in some other embodiments, DC- may also be between SW and DC+), so that the DC+ wiring area and the DC- wiring area are adjacent, providing convenience for the two to overlap.

[0287] To enhance DC+ and DC- overlap, vias are located on both ends of the DC+ routing area, connecting each layer, particularly the pad layer. This ensures sufficient DC+ and DC- overlap and evens out the current flow in this overlapped area. This also ensures that each soldering point within the long DC+ pad area has low impedance from the module interior, simplifying system layout.

[0288] Because the module disclosed in this embodiment is suitable for high-frequency applications, it is also necessary to reduce parasitic capacitance between the SW and DC+ or DC-. Therefore, the internal wiring of the multilayer PCB must avoid overlap between the SW and DC+ or DC-. Specifically, at least one inner layer of the multilayer PCB must have a clearance area at the SW end corresponding to the electrical connection pillar 16 to prevent overlap between the DC+ and SW. In the DC+ routing area, interlayer vias are placed on both sides of the clearance area and routed outside the clearance area.

[0289] In a preferred embodiment, the module contains at least one temperature sampling device TS. To facilitate wiring and ensure the temperature sampling effect, the temperature sampling device TS is placed on one of the left and right sides of the PCB, and in the middle of the upper and lower sides, that is, it is set in a position adjacent to the middle of the two power chips.

[0290] Since the module of this embodiment is highly integrated and the PCB undergoes multiple high-temperature soldering processes during the module production and use, the large-area wiring area of ​​the inner layer of the multi-layer PCB is provided with exhaust holes, that is, multiple openings with a diameter greater than 0.1 mm are provided, preferably with a diameter greater than 0.2 mm, to facilitate the release of moisture inside the PCB and avoid board explosion.

[0291] The embodiment of the present invention in which the front surface of all power chips is directly electrically connected to the PCB (the electrical connection distance from the chip electrode to the PCB is no longer than 1mm is called direct connection) is particularly suitable for Rsp less than 2mOhm / cm 2 Especially less than 1mOhm / cm 2 Devices, currently third-generation semiconductors such as SiC or GaN, or Si devices with a withstand voltage below 100V, with fourth- and fifth-generation semiconductors also possible in the future, can reduce package resistance to match the device's Rdson. The present invention also reduces distributed parameters and increases operating frequency. The operating frequency of the module in the present invention embodiment is preferably no less than 100 kHz, and preferably no less than 500 kHz.

[0292] In another preferred embodiment, as shown in Figure 13C , for planar devices—those with all power electrodes on the front side of the power die, such as GaN—the length of a planar device is typically at least 1.5 times its width to achieve low die internal resistance. The source electrode (S) and drain electrode (D) are arranged along the long sides, while the gate electrode (G) is adjacent to the source electrode (S). Figures 13D, 13E, and 13F illustrate the DBC metal layer layout and die arrangement (top view), PCB device layer layout (bottom view), and PCB pad layer layout (top view) of a full-bridge module, respectively. To reduce loop inductance, the two power dies forming the bridge arm are arranged parallel to each other with their long sides facing each other. The power electrodes between the two power dies are interconnected to form the SW electrode. Therefore, within the device layer, the wiring areas are arranged in the order of DC+, SW, and DC-, with the SW wiring area located between the DC+ and DC- wiring areas. The module's pad layout can also correspond to the order of the PCB device layer wiring areas, reducing power routing and parasitic capacitance between the SW terminal and the DC+ / DC- terminals. However, this makes it more difficult to couple the DC+ and DC- terminals through the wiring layer to reduce parasitic inductance. Planar devices typically switch very quickly, requiring lower loop inductance than vertical devices. Therefore, it is more meaningful to have a built-in loop decoupling capacitor (capacitor C). Capacitors C should be as small as possible and multiple capacitors should be provided. To minimize the added size of capacitors C, multiple capacitors C should be arranged in a nearly linear array along either the length or width direction, increasing only the width or length as little as possible. If multiple switching arms are provided within the half-bridge power module 1, the number of capacitors C can be set to at least one more than the number of switching arms. Since the arm decoupling capacitors are high-voltage capacitors and are often relatively large, they should be placed away from the DBC. As shown in Figure 13G, at least 50% of the capacitor C should not overlap with the DBC in the vertical direction.

[0293] When the module consists of a single half-bridge arm, the temperature sampling device TS can be placed near the outer side of the SW wiring after the two arm chips are interconnected. When the module contains multiple bridge arms, the temperature sampling device TS is placed in the middle of the four devices arranged in two rows and two columns. As a specific example, the 650V 50mOhm chip size is approximately 3mm*1.5mm, and the full-bridge DBC size is approximately 10mm*8mm, resulting in a final module size of approximately 14mm*12mm. Therefore, it is extremely small, less than one-third the size of existing solutions.

[0294] Example 11

[0295] This embodiment discloses a structure for a power module that integrates an isolated driver nearby. Due to its small size, a high-voltage insulated driver can be directly integrated. As shown in Figures 14A to 14C, to reduce the difficulty of packaging, the driver component 41 is only placed on the multi-layer circuit board 12 (i.e., PCB) and is not directly connected to the insulating heat-conducting plate 14 (i.e., DBC). Therefore, the driver component 41 should be placed outside the DBC in the horizontal direction. The area of ​​the DBC will then be significantly smaller than the size of the module. Therefore, in actual use, a temperature plate 141 with an area equivalent to that of the module can be connected to the DBC with low thermal resistance by welding or bonding with high thermal conductivity materials. The temperature plate 141 is surrounded by a plastic encapsulation body 13, and the width of the edges of the temperature plate 141 from the surface of the plastic encapsulation body 13 is not less than 0.4 mm to ensure that the plastic encapsulation material around the temperature plate can be included in the creepage distance. As shown in Figure 14A, if the temperature plate 141 is first connected to the DBC and then plastic encapsulated, then fixing columns 161 need to be provided to increase strength and resist mold flow. In some other embodiments, the DBC and the PCB may be connected and sealed first, and then the temperature balancing plate 141 may be provided.

[0296] Since the device size starting from the third generation is very small, the module size can also be very small, so the creepage distance of the high-voltage drive will become an obstacle to reducing the module size. Therefore, as shown in Figures 14B and 14C, this embodiment uses the mature fixed-depth groove process of PCB on the pad surface of the PCB, between the high-voltage side and the low-voltage side Pad, to prefabricate the isolation groove 121 with a width and depth of not less than 1mm to improve the creepage distance. Preferably, as shown in Figure 14D, multiple isolation grooves 121 can be provided in parallel to further improve the creepage distance.

[0297] This embodiment is particularly suitable for use in high-voltage isolation transformer applications. As shown in Figures 14E and 14F, in a high-voltage isolation transformer, at least a portion of the transformer windings are integrated into a system PCB. A half-bridge power module 1 is soldered to the system PCB and placed on the high-voltage side. The system PCB is provided with an opening to accommodate a magnetic core. The height of the magnetic core above the system PCB is approximately the same as the thickness of the half-bridge power module 1, and magnetic coupling with the windings achieves power conversion. When the half-bridge power module 1 of this embodiment is applied, the heat dissipation surface of the power devices on the high-voltage side is concentrated and regular. If the height of the magnetic core is designed to match the thickness of the half-bridge power module 1, the fixing of the heat sink 7 of the converter is much simpler and more reliable than traditional solutions. Because the heat sink 7 can be directly thermally connected to the magnetic core and the low-voltage side without insulation or only low-voltage insulation is required, and the half-bridge power module 1 also has built-in high-voltage isolation, the system requires almost no insulation when installing the heat sink, achieving extremely high reliability and heat dissipation capabilities.

[0298] Even if some low-heat-generating components (small heat sources) cannot be integrated, heat conduction can be easily achieved through traditional means, such as providing a thermal pad 72 and an insulating thermal conductor 71. When the thickness of the half-bridge power module 1 meets the lateral creepage distance requirements, as shown in Figure 14E, the heat sink 7 and the half-bridge power module 1 can be directly thermally connected using low-voltage and low-thermal resistance materials. When the thickness of the half-bridge power module 1 does not meet the lateral creepage distance requirements, as shown in Figure 14F, the heat sink 7 and the half-bridge power module 1 can be thermally connected via an insulating thermal conductor 71 that meets safety regulations.

[0299] Example 12

[0300] In this embodiment, the power electrode on the back of the power chip is guided from the DBC to the PCB through the electrical connection column 16, or the front electrode of the power chip is raised through the electrical connection column 17 to facilitate mold flow entry. As shown in Figure 15, when a high-frequency current flows through at least one of the electrical connection columns 16 and 17, current sampling integration can be achieved by providing a current sampling winding 30 around the electrical connection column 16 / 17. In a preferred embodiment, the current sampling winding 30 can be formed by prefabricating the winding on the electrical connection column 16 / 17, or by etching the welding surface around the electrical connection column 16 / 17 on the PCB, and then the current sampling winding 30 is electrically connected to a current sampling circuit (set in an independent chip or integrated with other circuits) to process the sampling signal. The current sampling circuit can be provided with a correction function, and the sampling coefficient can be systematically corrected when the power module undergoes factory testing to achieve high-precision sampling.

[0301] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0302] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A packaging structure of a half-bridge power module, characterized in that: It includes an insulating heat-conducting plate, a multi-layer circuit board, a packaging filling body and a bridge arm switch, wherein the bridge arm switch includes an upper bridge arm switch and a lower bridge arm switch, wherein the upper bridge arm switch and the lower bridge arm switch each include at least one power element, wherein the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface; The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit, and the packaging filling body fills the area between the insulating heat-conducting plate and the multi-layer circuit board and covers the bridge arm switch; The pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

2. The packaging structure according to claim 1, characterized in that: The pin pads also include NC pads.

3. The packaging structure according to claim 1, characterized in that: The power pad includes a half-bridge positive pad, a half-bridge negative pad and a half-bridge midpoint pad; the half-bridge positive pad is electrically connected to one end of the half-bridge circuit, and the half-bridge negative pad is electrically connected to the other end of the half-bridge circuit; the circuit node between the upper arm switch and the lower arm switch of the same half-bridge circuit is the half-bridge midpoint end, and the half-bridge midpoint pad is electrically connected to the half-bridge midpoint end.

4. The packaging structure according to claim 3, characterized in that: The pad surface has a first edge, a second edge, a third edge, and a fourth edge that are adjacent to each other in sequence; the half-bridge midpoint end pad is arranged near the first edge and is adjacent to the second edge and the fourth edge; the half-bridge negative end pad is arranged near the third edge and is adjacent to the second edge and the fourth edge; the half-bridge positive end pad is arranged between the half-bridge midpoint end pad and the half-bridge negative end pad and is adjacent to the second edge and the fourth edge.

5. The packaging structure according to claim 3, characterized in that: At least two half-bridge circuits are arranged in the packaging structure; on the pad surface, the pin pads are arranged in an array along the first direction according to the corresponding relationship between the half-bridge circuits, and the pin pads are arranged along the second direction according to the circuit function correspondence between the half-bridge midpoint pad, the half-bridge positive pad and the half-bridge negative pad; the half-bridge positive pads corresponding to the half-bridge circuits are arranged in the same row along the first direction, and the half-bridge negative pads corresponding to the half-bridge circuits are arranged in another same row along the first direction.

6. The packaging structure according to claim 1, characterized in that: At least one of the pin pads is a grid-shaped pad, and each of the grid-shaped pads includes a plurality of sub-pads arranged in an array and electrically connected to each other in the packaging structure.

7. The packaging structure according to claim 1, characterized in that: The signal loop pads are arranged in pairs or groups, and each pair or group of signal loop pads is arranged in a pad surface sub-area or shares a pad surface sub-area with a power pad; each power pad is arranged in one or more pad surface sub-areas; the number of pad surface sub-areas provided with pin pads accounts for at least two-thirds of the total number of all pad surface sub-areas.

8. The packaging structure according to claim 7, characterized in that: A pin pad is arranged in each pad surface area, and the area of ​​the pin pad in each pad surface area accounts for no less than 15%.

9. The packaging structure according to claim 1, characterized in that: The power electrodes of the bridge arm switches are electrically connected via a multi-layer circuit board.

10. The packaging structure according to claim 1, characterized in that: The pin pads also include a Sink pad, which is electrically connected to the heat dissipation surface and is used to electrically connect the heat dissipation surface to an electrostatic potential.

11. The packaging structure according to claim 1, characterized in that: The insulating heat-conducting plate is a copper-clad ceramic substrate; the upper bridge arm switch and the lower bridge arm switch corresponding to the same half-bridge circuit are respectively arranged on a group of switch copper-clad areas on the insulating heat-conducting plate, and the switch copper-clad areas include an upper switch copper-clad area and a lower switch copper-clad area, the upper bridge arm switch is electrically connected to the upper switch copper-clad area, and the lower bridge arm switch is electrically connected to the lower switch copper-clad area; the upper switch copper-clad area and the lower switch copper-clad area are adjacently arranged, and the corresponding edges of the upper switch copper-clad area and the lower switch copper-clad area are serrated and zigzag when they are adjacently arranged.

12. The packaging structure according to claim 11, characterized in that: It also includes an electrical connection column, the two ends of which are electrically connected to the insulating heat-conducting plate and the multi-layer circuit board respectively; the packaging filling body covers the electrical connection column; and at least one of the electrical connection columns is located at the tooth-shaped meandering setting.

13. The packaging structure according to claim 1, characterized in that: The multilayer circuit board is a first PCB board, and the insulating heat-conducting board is a second PCB board; the second PCB board includes at least two wiring layers and at least one insulating medium layer; and the thermal conductivity of the insulating medium layer of the second PCB board is greater than 1.

14. The packaging structure according to claim 1, characterized in that: The bridge arm switch includes at least one of a MOS switch, an IGBT element with an anti-parallel diode, a thyristor and a DIO diode.

15. The packaging structure according to claim 1, characterized in that: The bridge arm switch includes at least one of a SiC device and a GaN device.

16. The packaging structure according to claim 1, characterized in that: The bridge arm switch is a vertical device, and power electrodes with different electrical properties are respectively arranged on the upper surface and the lower surface of the vertical device.

17. The packaging structure according to claim 1, characterized in that: It also includes an active temperature signal element, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad; The active temperature signal element includes a temperature measurement unit, a signal processing unit, an output enable unit and an output switch device; one end of the temperature measurement unit is set to be grounded; the temperature measurement unit, the signal processing unit, the output switch device and the temperature signal pad are connected in series in sequence; the output switch device has a first end, a second end and a control end, the first end is electrically connected to the output end of the signal processing unit, and the second end is electrically connected to the temperature signal pad; the output enable unit controls the control end by comparing the potentials of the first end and the second end.

18. The packaging structure according to claim 1, characterized in that: It also includes a temperature-sensitive Zener diode, which is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the packaging filling body covers the active temperature signal element; the signal loop pad includes a temperature signal pad; one end of the Zener diode is set to be grounded, and the other end is electrically connected to the temperature signal pad.

19. The packaging structure according to claim 1, characterized in that: A packaging filling groove is opened at the edge of the multilayer circuit board; the packaging filling body fills the packaging filling groove.

20. The packaging structure according to claim 19, characterized in that: The side surface of the packaging filling body is provided with a creepage bulge or a creepage groove.

21. The packaging structure according to claim 20, characterized in that: The side surface of the packaging filling body is provided with a creepage bulge or a creepage groove, the horizontal extension length of which is not less than 1 mm.

22. The packaging structure according to claim 19, characterized in that: The thickness of the exposed portion of the side surface of the multilayer circuit board does not exceed 1 mm.

23. The packaging structure according to claim 1, characterized in that: The bottom surface of the insulating heat-conducting plate is also provided with a thick heat-conducting metal layer, and the packaging filling body covers the side surfaces of the thick heat-conducting metal layer.

24. The packaging structure according to claim 1, characterized in that: It also includes a fixing column, both ends of which are fixedly connected to the insulating heat-conducting plate and the multi-layer circuit board respectively.

25. The packaging structure according to claim 24, characterized in that: The insulating heat-conducting plate is divided into four quadrant areas in the horizontal direction, and at least one fixing column is arranged between the insulating heat-conducting plate and the multi-layer circuit board corresponding to each quadrant area.

26. The packaging structure according to claim 24, characterized in that: The multilayer circuit board is electrically connected to the fixing column and the power element respectively by welding, the height of the fixing column is Hpole, the sum of the thickness of the power element and its front electrode is Hdie, and Hdie-Hpole≥20μm.

27. The packaging structure according to claim 26, characterized in that: The area of ​​the steel mesh opening corresponding to the solder arranged on the fixing column in the welding process is not less than 120% of the welding area of ​​the top end of the fixing column.

28. The packaging structure according to claim 24, characterized in that: The total welding area of ​​the top end of the fixing column is not less than 2% of the area of ​​the insulating heat-conducting plate.

29. The packaging structure according to claim 1, characterized in that: The multilayer circuit board includes at least four wiring layers; each of the wiring layers is provided with a DC-wiring area, a DC+ wiring area and a SW wiring area arranged in sequence in one direction, or each of the wiring layers is provided with a DC+ wiring area, a DC- wiring area and a SW wiring area arranged in sequence in one direction; the four wiring layers include a first wiring layer and a second wiring layer, the first wiring layer and the second wiring layer are adjacent, the DC+ wiring area arranged in the first wiring layer is a large-area DC+ wiring area, the DC- wiring area arranged in the second wiring layer is a large-area DC- wiring area, and at least 10% of the projections of the large-area DC+ wiring area and the large-area DC- wiring area overlap with each other.

30. The packaging structure according to claim 29, characterized in that: It also includes a plurality of electrical connection columns, both ends of which are electrically connected to the insulating heat conductive plate and the multilayer circuit board respectively; the packaging filling body covers the electrical connection columns; the power element includes at least one vertical power chip; the electrical connection columns are arranged in parallel between the power elements.

31. The packaging structure according to claim 30, characterized in that: The electrical connection column includes a SW end electrical connection column, and the SW end electrical connection column is electrically connected to the SW wiring area. The position corresponding to the SW end electrical connection column in the multi-layer circuit board is an avoidance area, and at least one of the DC+ wiring areas is arranged to bypass the avoidance area, or at least one of the DC- wiring areas is arranged to bypass the avoidance area.

32. The packaging structure according to claim 31, characterized in that: When at least one of the DC+ wiring areas is set up to bypass the avoidance area, the DC+ wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pads corresponding to the DC+ wiring area are long strips spanning the avoidance area; or, when at least one of the DC- wiring areas is set up to bypass the avoidance area, the DC- wiring area is provided with interlayer electrical connectors on both sides of the avoidance area, and the power pads corresponding to the DC- wiring area are long strips spanning the avoidance area.

33. The packaging structure according to claim 29, characterized in that: It also includes at least one temperature sampling element, which is arranged between the upper bridge arm switch and the lower bridge arm switch in the direction of the connection line between the upper bridge arm switch and the lower bridge arm switch, and the temperature sampling element is arranged on one side of the multilayer circuit board in a direction perpendicular to the connection line between the upper bridge arm switch and the lower bridge arm switch.

34. The packaging structure according to claim 1, characterized in that: The power element includes at least one third-generation power semiconductor element or a low-voltage silicon power semiconductor element, or the Rsp of the power element does not exceed 2mOhm / cm 2 , the operating frequency of the board bridge power module is at least 100kHz.

35. The packaging structure according to claim 1, characterized in that: The power element includes at least two planar power semiconductor elements, and the aspect ratio of the planar power semiconductor elements is at least 1.

5.

36. The packaging structure according to claim 35, characterized in that: The at least two planar power semiconductor devices are arranged in parallel with their long sides and are interconnected by points to form at least one bridge arm. The multilayer circuit board includes a SW wiring area, a DC+ wiring area and a DC- wiring area, and the SW wiring area is arranged between the DC+ wiring area and the DC- wiring area.

37. The packaging structure according to claim 29 or 36, characterized in that: At least one of the DC-wiring area, the DC+wiring area, and the SW wiring area is provided with an exhaust hole, and a diameter of the exhaust hole is greater than 0.1 mm.

38. The packaging structure according to claim 36, characterized in that: It also includes at least two bridge arm decoupling capacitors, wherein the bridge arm decoupling capacitors are arranged at positions avoiding the insulating heat conducting plate, and the bridge arm decoupling capacitors are arranged in a straight line.

39. The packaging structure according to claim 35, characterized in that: The power element includes at least four planar power semiconductor elements, which are arranged in 2 rows and 2 columns; the packaging structure also includes a temperature sampling unit, which is arranged in the middle of the at least four planar power semiconductor elements.

40. The packaging structure according to claim 1, characterized in that: It also includes a high-voltage isolation drive component, which is arranged on a multi-layer circuit board. The high-voltage isolation drive component is arranged on one side of the insulating heat-conducting plate and avoids the insulating heat-conducting plate.

41. The packaging structure according to claim 40, characterized in that: It also includes a temperature averaging plate, which is arranged on the heat dissipation surface, and the temperature averaging plate is connected to the insulating heat conducting plate with low thermal resistance.

42. The packaging structure according to claim 41, characterized in that: The packaging filling body covers the edges of the temperature equalizing plate and the thickness of the covering is at least 0.4 mm.

43. The packaging structure according to claim 42, characterized in that: It also includes a fixing column, both ends of which are fixedly connected to the temperature averaging plate and the multi-layer circuit board respectively.

44. The packaging structure according to claim 41, characterized in that: The temperature homogenizing plate is arranged outside the packaging filling body.

45. The packaging structure according to claim 40, characterized in that: An isolation groove is provided on the pad surface of the multilayer circuit board, the width and depth of the isolation groove are both not less than 1 mm, and the isolation groove is used to increase the creepage distance between the high-voltage side and the low-voltage side.

46. ​​The packaging structure according to claim 45, characterized in that: The isolation grooves are arranged in a plurality.

47. The packaging structure according to claim 40, characterized in that: The high-voltage isolation driving component includes at least two driving chips; the driving chips are electrically connected through bonding wires, or the driving chips are planar driving chips and the driving chips are electrically connected through a multi-layer circuit board.

48. The packaging structure according to claim 1, characterized in that: It also includes an electrical connection column and a current sampling winding, wherein the current sampling winding is provided with at least one turn around the electrical connection column, the current sampling winding is used to sample the high-frequency current passing through the electrical connection column, and the current sampling winding is electrically connected to a current sampling circuit.

49. The packaging structure according to claim 48, characterized in that: The current sampling winding is arranged in a multi-layer circuit board, or is preformed with the electrical connection column to form an assembly.

50. The packaging structure according to claim 48, characterized in that: The current sampling circuit is provided with a correction function.

51. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: include: Welding a plurality of the packaging structures onto the same PCB substrate; A fixed housing and a common heat sink are provided, wherein the fixed housing is used to fix the common heat sink, and the fixed housing includes a cover plate located at the back side of the PCB substrate; A pressure ejector pin is arranged between the cover plate and the PCB substrate, and the position of the pressure ejector pin corresponds to the packaging structure; The common heat sink is pressed onto a plurality of packaging structures through the fixed shell, and during pressing, the PCB substrate is deformed by the pressure ejector pins so as to absorb the tolerance of each packaging structure in the thickness direction.

52. An application of the packaging structure of the half-bridge power module according to any one of claims 1 to 50, characterized in that: include: Welding a plurality of the packaging structures onto the same PCB substrate; A fixed shell and liquid-cooled radiators corresponding to the number of the packaging structures are provided. The fixed shell is used to press and fix the liquid-cooled radiators and the corresponding packaging structures. The fixed shell includes a heat dissipation liquid pipeline, an interface hose and a pressure elastic member; the interface hose is used to connect the liquid path between the heat dissipation liquid pipeline and the liquid-cooled radiators, so that the heat dissipation liquid pipeline and each liquid-cooled radiator form a connected integral liquid path. The liquid-cooled radiator is pressed and fixed on multiple packaging structures through the fixed shell. During pressing, the fixed shell applies pressure in the pressing and fixing direction to the liquid-cooled radiator through the pressure elastic member. The pressure elastic member and the interface hose absorb the tolerance of each packaging structure in the thickness direction through deformation.

53. An application of the packaging structure of the half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to an on-board OBC power converter, which includes a substrate and at least two of the half-bridge power modules. At least one power pin between the two half-bridge modules is electrically short-circuited through a system-side multilayer circuit board. The substrate includes a first component area, a second component area, and a third component area, which are arranged in sequence. The first component area is provided with a capacitor and a controller, the second component area is provided with the half-bridge power module, the heat dissipation surface of the half-bridge power module is provided with a heat sink, the third component area is provided with a transformer and an inductor, the winding of the inductor is integrated in the substrate, or the winding of the inductor is independently heat-dissipated and insulated from the iron core through cavity encapsulation of insulating thermal conductive glue, and the driving component corresponding to the bridge arm switch is arranged on the other side of the substrate corresponding to the half-bridge power module.

54. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a DCDC isolation converter, which includes a substrate, a transformer core and at least one half-bridge power module. The half-bridge power module is an input side module and / or an output side module. The transformer core is buckled on the substrate, and the winding corresponding to the transformer core is integrated in the substrate. The input side module and the output side module are respectively arranged on both sides of the transformer core. The heat dissipation surfaces of at least a part of the half-bridge power modules share a heat sink, and an insulating heat conductive member is arranged between the transformer core and the heat sink.

55. The application of the packaging structure of the half-bridge power module according to claim 54, characterized in that: The DCDC isolation converter further includes a secondary insulation processing structure, and the secondary insulation processing structure is a secondary plastic packaging body or a glue filling structure.

56. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: Applying the half-bridge power module to a non-isolated power converter, wherein the non-isolated power converter comprises a substrate, an inductor element and at least one half-bridge power module; The half-bridge power module is arranged on a substrate; The inductor element is arranged in parallel with the assembly of the half-bridge power module and the substrate, or the inductor element is arranged in parallel with the half-bridge power module on the substrate; The half-bridge power module and the inductor element share a heat sink, and the inductor element and the heat sink are directly provided with insulating heat conducting members.

57. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a cardiac arrest awakening device, which includes a shell, a first PCBA component layer, a second PCBA component layer and a filling glue. The first PCBA component layer and the second PCBA component layer are stacked in the shell, and the filling glue is filled in the gap between the shell, the first PCBA component layer and the second PCBA component layer; the first PCBA component layer includes a power supply element and a power supply drive element, and the second PCBA component layer includes at least one half-bridge power module, and at least one half-bridge power module is used to generate a high-voltage pulse output, and the heat dissipation surface of the half-bridge power module is in contact with the shell.

58. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a large IPM module, including: The heat dissipation surfaces of the multiple packaging structures are fixedly connected to the heat sink; they are soldered to the first PCB substrate through SMD; module circuit elements are arranged on the other side of the first PCB substrate; the module circuit elements include at least one of a control unit, a driving unit and a decoupling capacitor.

59. The use according to claim 58, characterized in that The large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting a plurality of bidirectional switch bridge arms in parallel.

60. An application of the packaging structure of a half-bridge power module according to any one of claims 1 to 50, characterized in that: The half-bridge power module is applied to a large IPM module, including: The heat dissipation surfaces of the plurality of packaging structures are fixedly connected to a heat sink; they are soldered to a first PCB substrate through SMD; a second PCB substrate is provided, and module circuit elements are arranged on the second PCB substrate; the module circuit elements include at least one of a control conductor, a driving unit and a decoupling capacitor; the second PCB substrate and the first PCB substrate are electrically connected through elastic pins.

61. The use according to claim 60, characterized in that The large IPM module is at least one of a high-power half-bridge circuit, a high-power full-bridge circuit, a high-power three-phase bridge circuit, an ANPC circuit, a TNPC circuit, a Heric circuit, or a solid-state relay circuit formed by connecting a plurality of bidirectional switch bridge arms in parallel.

62. The application of the packaging structure of the half-bridge power module according to claim 60, characterized in that: Also includes: Decoupling capacitors are arranged between and outside the packaging structures, and the decoupling capacitors are arranged on the heat sink through a thermal pad and are electrically connected to the first PCB substrate; A Vbus capacitor is arranged on the first PCB substrate; the Vbus capacitor is arranged adjacent to the assembly of the decoupling capacitor, the packaging structure and the heat sink.

63. The application of the packaging structure of the half-bridge power module according to claim 60, characterized in that: Also includes: A decoupling capacitor and an elastic pin are arranged on a surface of the first PCB substrate facing the second PCB substrate; A cover plate is installed on the first PCB substrate, the cover plate covers the decoupling capacitor, and the upper ends of the elastic pins extend out of the cover plate.

64. Application of the packaging structure of the half-bridge power module according to claim 62 or 63, characterized in that: Also includes: A suspended pad is provided on the surface of the first PCB substrate facing the second PCB substrate, the suspended pad is adjacent to a circuit node pad corresponding to a circuit node corresponding to one pin of a decoupling capacitor, the decoupling capacitor and the suspended pad are electrically connected, and an open circuit is maintained between the suspended pad and the corresponding circuit node pad; The leakage current of the packaging structure is tested, and after the test is qualified, the suspended pad is electrically connected to the corresponding circuit node pad.

65. An application of the packaging structure of the half-bridge power module according to any one of claims 3 to 5, characterized in that: The half-bridge power module is applied to an ANPC circuit, wherein the ANPC circuit includes a plurality of ANPC sub-units arranged in parallel, wherein the ANPC sub-units include a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, wherein the arm switches of the first half-bridge power module and the second half-bridge power module are both IGBT elements of anti-parallel diodes, and the first half-bridge power module and the second half-bridge power module are connected in series; The bridge arm switch of the third half-bridge power module is a MOS switch or an IGBT element of an anti-parallel diode, the half-bridge positive end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the third half-bridge power module is electrically connected to the half-bridge midpoint end pad of the second half-bridge power module.

66. An application of the packaging structure of the half-bridge power module according to any one of claims 3 to 5, characterized in that: The half-bridge power module is applied to a TNPC circuit, the TNPC circuit includes a plurality of TNPC sub-units arranged in parallel, the TNPC sub-units include a first half-bridge power module and a second half-bridge power module, the second half-bridge power module is a bidirectional switch module, the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the half-bridge positive end pad of the bidirectional switch module is electrically connected to the half-bridge midpoint end pad of the first half-bridge power module, and the half-bridge negative end pad of the bidirectional switch module is grounded.

67. An application of the packaging structure of the half-bridge power module according to any one of claims 3 to 5, characterized in that: The half-bridge power module is applied to the Heric circuit. The Heric circuit includes a first half-bridge power module, a second half-bridge power module and a third half-bridge power module, wherein the third half-bridge power module is a bidirectional switch module, and the half-bridge midpoint end of the bidirectional switch module does not participate in the circuit connection outside the bidirectional switch module; the first half-bridge power module and the second half-bridge power module are connected in parallel through the half-bridge positive end pad and the half-bridge negative end pad, and the bidirectional switch module is bridged between the half-bridge midpoint end pad corresponding to the first half-bridge power module and the half-bridge midpoint end pad of the second half-bridge power module.

68. A method for manufacturing a packaging structure of a half-bridge power module, characterized in that: The steps are as follows: S1: Assemble and fix the insulated heat conducting plate, multi-layer circuit board and bridge arm switch; S2: an overflow area is provided below the insulating heat conductive plate, and a space between the insulating heat conductive plate and the multilayer circuit board and the overflow area are simultaneously filled with a packaging filler, so that mold flow impacts of the upper and lower surfaces of the insulating heat conductive plate during packaging filling are offset, and a packaging filling body is formed in the space between the insulating heat conductive plate and the multilayer circuit board and the overflow area; S3: removing the packaging filling body in the overflow area by grinding; The bridge arm switch comprises an upper bridge arm switch and a lower bridge arm switch, each of the upper bridge arm switch and the lower bridge arm switch comprises at least one power element, the lower surface of the packaging structure is a heat dissipation surface, and the upper surface of the packaging structure is a pad surface; The insulating heat-conducting plate is arranged at the bottom of the packaging structure, the multi-layer circuit board is arranged at the top of the packaging structure and one surface of the multi-layer circuit board is the pad surface, the bridge arm switch is arranged between the insulating heat-conducting plate and the multi-layer circuit board, and the upper bridge arm switch and the lower bridge arm switch are electrically connected to form a half bridge circuit.

69. The method according to claim 68, characterized in that: The pad surface is equally divided into n×m pad surface sub-areas, n and m are both greater than or equal to 2, the pad surface is provided with pin pads, and the pin pads include power pads and signal loop pads; the power pads are electrically connected to the half-bridge circuit; the signal loop pads are used for signal reporting and / or signal control of the bridge arm switch; the pin pads are distributed in at least one-half of the pad surface sub-areas; the total area of ​​the pin pads accounts for no less than 15% of the total area of ​​the pad surface.

70. The method according to claim 68, characterized in that: The thickness of the packaging filling body in the overflow area is not less than 0.3 mm.

71. The method according to claim 68, characterized in that: The heat dissipation surface is the back side of the insulating heat conductive plate. The back side of the insulating heat conductive plate is provided with back side copper cladding. In step S1, the thickness of the back side copper cladding is not less than 150 μm.

72. The method according to claim 71, characterized in that: Step S3 also includes: thinning the back copper coating by grinding.

73. The method according to claim 71, characterized in that: The front side of the insulating heat conductive plate is provided with front copper cladding. In step S1, the thickness of the front copper cladding is smaller than the thickness of the back copper cladding. The difference between the thickness of the front copper cladding and the thickness of the back copper cladding is at least 50 μm.

74. The method according to claim 72, characterized in that: After step S3 , the thickness tolerance of the packaging structure does not exceed 100 μm.

Images