Pin-free semiconductor integrated power module and application terminal

Abstract

The utility model relates to the technical field of power semiconductors, in particular to a pin-free semiconductor integrated power module and application terminal, which comprises a shell and a substrate, the substrate comprises an insulating plate and a first metal layer covered on one surface of the insulating plate, the shell is packaged on the substrate, the first metal layer faces the shell, and the first metal layer faces the first metal layer. The first metal layer is provided with a connecting bonding pad on the outer side of the shell, and the surface of the connecting bonding pad is covered with a protective layer. According to the utility model, the pin-free semiconductor integrated power module is directly connected with the outside through the connection bonding pad, thereby reducing conductive paths, improving the reliability of electrical connection, reducing the risk of poor contact caused by pin dimensional tolerance, welding process deviation and the like, improving parasitic inductance and capacitance in a pin connection mode, and improving the reliability of the power module. Electrical parameters such as electromagnetic compatibility, a safe working area and the like of the power module are optimized, and stability and durability of the module in a high-vibration environment are enhanced at the same time.

Description

TECHNICAL FIELD

[0001] The utility model relates to power semiconductor technical field especially relates to a leadless semiconductor integrated power module and application terminal. BACKGROUND

[0002] Power module, through power chip, with certain electrical layout, through external pin carries out power output and control. The existing power module, no matter what kind of packaging form's power module, such as QFP package module (four side flat package module), DPIM package (see patent CN220556592U), PIM power module (see patent CN216086502U) etc., all carry out internal and external power inversion and input / output through power pin / terminal, realize internal and external electrical connection of power module. In the traditional DPIM package module, HPD package module's power pin / terminal after chip soldering and wire bonding, through soldering, ultrasonic bonding etc. mode, weld power pin / terminal on the electrical layer substrate, realize internal and external electrical connection of power module. And for example QFP package module (four side flat package module), PIM power module (see CN216086502U) etc. form's package module, in its process, need to design corresponding special lead frame, and after chip soldering, through the way of bonding wire and power pin / terminal connection, and through epoxy resin encapsulation, complete corresponding electrical function.

[0003] Take DPIM power module as an example, it mainly includes DBC substrate, power chip, bonding wire, power terminal and plastic encapsulation glue, and power pin, often after power chip bonding and wire bonding, through solder and / or soldering pad welding to the DBC electrical layer where the chip is, or through ultrasonic bonding method, directly bonding power pin to the DBC electrical layer where the chip is, thereby complete the installation of the "bridge" of internal and external communication of power module, then through plastic encapsulation glue filling process, use plastic encapsulation insulation glue to encapsulate power module. The conventional welding and / or bonding power pin / terminal process or structure of this existing power module, at least has the following technical problems:

[0004] (1) Due to the complexity of the electrical structure of the power module and the functions it implements, as well as the external connection requirements, many power pins are needed to work together to achieve different functions of the power module, such as the control terminals connected to the G / E poles of the power chip, the thermistor terminals connected to the thermistor, the three-phase output terminals, the current input / output terminals, etc. The number is large and the arrangement is close, which makes the power pins vulnerable to the welding / bonding environment during welding / bonding, making it difficult for each power pin to be aligned, resulting in misaligned welding / bonding of power pins, and further causing the power pins to not be able to connect with the specified location of the PCB during terminal application or not to be fully connected, resulting in low reliability of the power module and poor terminal application effect. Moreover, the use of welding / bonding for power pins also has the problem of poor welding caused by welding voids or virtual pressure, incomplete welding / bonding, and incomplete solder contact, which can cause the power pins to fall off, seriously affecting the use of the power module and causing cost loss.

[0005] (2) Based on the DPIM power module, the resin plastic sealing glue is used for packaging. After the welding / bonding of the power pins is completed, the silicone gel is poured into the module for packaging through a customized mold or equipment. Due to the easy flowability and good adhesion of the glue, there is silicone attached to the bottom of the power pins of the packaged power module, which seriously affects the subsequent terminal application and the performance of the power module. Moreover, further cleaning of the attached silicone is needed, which affects production efficiency.

[0006] (3) Whether the power pins are welded or bonded, appropriate equipment and materials are needed, and the connection state after the power pins are installed needs to be detected by appropriate equipment and testing methods, such as welding void detection and push-pull force testing. Moreover, after the final encapsulation is completed, further cleaning of the attached silicone is needed, which is a complex process and is not conducive to cost control. Other types of packaging modules, such as QFP packaging modules and SMD packaging modules (see CN102790043B), use different packaging materials than DPIM, and the packaging materials used are epoxy resin, but most of the processes are similar, but there are still the above technical problems.

[0007] Therefore, the power terminals / pins of the power module on the market are connected with the metal lead frame carrying the power chip through bonding wires or soldered lead wires, and there is also a situation that the power terminals fall off due to poor wire bonding or soldering during epoxy encapsulation, thereby causing failure of the power module. On the other hand, due to the close arrangement of the power pins, the electromagnetic loops interfere with each other, and in the pin bonding wire type power module, different shapes and lengths of metal connecting power pins need to be selected according to the application scene, which inevitably increases the length of the electric loop, generates larger parasitic inductance and parasitic capacitance, increases power loss and introduces strong electromagnetic interference during application, causes voltage overshoot during high-frequency switching of the power module, damages the power module due to transient voltage peak exceeding rated value, narrows the safe working area of the power module, and reduces insulation and reliability. Content of the utility model

[0008] Therefore, the purpose of the utility model is to provide a pinless semiconductor integrated power module and an application terminal to at least solve the problems of existing power modules with power terminals / pins, such as increased power loss and introduced strong electromagnetic interference during application, and damaged power module due to transient voltage peak exceeding rated value, narrowed safe working area of the power module, and reduced insulation and reliability.

[0009] The utility model solves the above technical problems through the following technical means:

[0010] The first aspect of the utility model is to provide a pinless semiconductor integrated power module, which comprises:

[0011] A shell;

[0012] A substrate comprising an insulating plate and a first metal layer covering one surface of the insulating plate, the shell being packaged on the substrate, the first metal layer facing the shell, the first metal layer being provided with a connection pad on the outside of the shell, and the surface of the connection pad being covered with a protective layer.

[0013] In combination with the first aspect, in some embodiments, the thickness of the protective layer is 1-3 microns.

[0014] In combination with the first aspect, in some embodiments, the first metal layer is used to set a circuit arrangement structure, the first metal layer inside the shell has an electrical gap for the circuit arrangement structure, and the power chip is soldered on the first metal layer inside the shell.

[0015] In combination with the first aspect, in some embodiments, the power chip is selected from at least one of a diode, a triode, a MOSFET, an IGBT, an FRD, an SIC, and a GAN.

[0016] In some embodiments, the other surface of the insulating plate is covered with a second metal layer, and the first metal layer and the second metal layer are located on opposite surfaces of the insulating plate, respectively.

[0017] In some embodiments, the first metal layer and the second metal layer are both copper foil layers.

[0018] The second aspect of the utility model provides a kind of application terminal, and the application terminal includes the pinless semiconductor integrated power module of the first aspect described above.

[0019] In some embodiments of the second aspect, the application terminal further includes a PCB board, the PCB board has a mounting hole, the shell penetrates the mounting hole, and the PCB board is welded with the connecting pad.

[0020] In some embodiments of the second aspect, the application terminal further includes a heat sink, the heat sink is fixedly connected with the PCB board, and the second metal layer faces the heat sink.

[0021] Compared with the prior art, the utility model has the following beneficial effects:

[0022] (1) the pinless semiconductor integrated power module of the utility model uses the connecting pad in the first metal layer on the substrate for electrical internal and external connection, removes the layout of the pins of conventional various packaging modules, and the overall size design is compact, which can achieve higher power density, is conducive to the dispersion layout of semiconductor chips on the substrate, reduces heat concentration, and improves the outflow capacity of the power module;

[0023] (2) the pinless semiconductor integrated power module of the utility model directly connects externally through the connecting pad, reduces the conductive path, improves the reliability of electrical connection, reduces the risk of poor contact caused by pin size tolerance, welding process deviation and the like, improves the parasitic inductance and capacitance of pin connection mode, optimizes the electromagnetic compatibility of the power module, electrical parameters such as safe working area, and at the same time enhances the stability and durability of the module in high-vibration environment;

[0024] (3) the pinless semiconductor integrated power module of the utility model is locally packaged by the shell, can accurately protect the chips and binding wire parts as needed, avoids the influence of packaging materials on other parts, and is flexible and simple in appearance; BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a structure schematic view of a pinless semiconductor integrated power module of the utility model;

[0026] Figure 2 is a split structure schematic view of a pinless semiconductor integrated power module of the utility model;

[0027] Figure 3 is a schematic diagram of a pinless semiconductor integrated power module and a PCB board connection;

[0028] Figure 4 is a schematic diagram of a pinless semiconductor integrated power module and a PCB board and a heat sink connection;

[0029] Wherein, the shell 110, the substrate 120, the first metal layer 121, the insulating plate 122, the connecting pad 123, the protective layer 124, the second metal layer 125, the power chip 130, the PCB board 200, the mounting hole 210, the heat sink 300, the bolt 400. DETAILED DESCRIPTION

[0030] The advantages and effects of the present application can be understood by the skilled in the art from the disclosure of the specification. It should be noted that the drawings provided in the following examples are only used for illustrative purposes, and the representation is only a schematic diagram, not a physical drawing, and should not be understood as a limitation of the present application. In order to better illustrate the embodiments of the present application, some components in the drawings may be omitted, enlarged or reduced, and do not represent the actual size of the product; for those skilled in the art, it is understandable that some well-known structures and their descriptions may be omitted.

[0031] The same or similar reference numerals in the drawings of the embodiments of the present application correspond to the same or similar components. In the description of the present application, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate the orientation or positional relationship shown in the drawings, they are only used for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms used to describe the positional relationship in the drawings are only used for illustrative purposes, and cannot be understood as a limitation of the present application. For those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0032] The pinless semiconductor integrated power module of the present application does not set pins, directly connects the connecting pads in the first metal layer on the substrate with external PCB boards for electrical connection, solves the problems that in the existing power module, the pins or power terminals are set, the power terminals or pins are caused to fall off due to poor wire bonding or welding, resulting in power module failure, power loss increase and strong electromagnetic interference during application, voltage overshoot during high-frequency switching of the power module, resulting in transient voltage peak exceeding rated value damaging the power module, also causing the safety working area of the power module to become narrow, insulation to decrease and reliability to decrease, etc.

[0033] Please refer toFigures 1-4 A no-pin semiconductor integrated power module and an application terminal will be described in detail below through specific embodiments of the utility model:

[0034] The utility model relates to a no-pin semiconductor integrated power module, which comprises a shell 110 and a substrate 120, the substrate 120 comprises an insulating plate 122 and a first metal layer 121 covering one surface of the insulating plate 122, the shell 110 is packaged on the substrate 120, the first metal layer 121 faces the shell 110, the first metal layer 121 is provided with a connecting pad 123 on the outside of the shell 110, and the surface of the connecting pad 123 is covered with a protective layer 124.

[0035] The shell 110 is made of an electrically insulating material, for example, the electrically insulating material can be hard plastic, silicone gel, epoxy resin, etc., which is used for electrical packaging of the power module to ensure the stability of the electrical work inside the power module. In particular, when the shell 110 is made of epoxy resin, metal heat sinks can be arranged on the non-direct packaging surface of the epoxy resin, including but not limited to copper sheets, aluminum sheets, etc., to further improve the heat dissipation capacity of the power module. When the shell 110 is a hard plastic shell, the packaging mode of the power module is local packaging of the intermediate circuit, and the packaging morphology is solid formed, which has certain mechanical strength to meet the electrical insulation, position fixation and environmental isolation protection of the module, avoiding the influence of the packaging material on other parts.

[0036] The substrate 120 can be selected from ceramic substrates with electrical transmission and insulation heat dissipation, such as a thin film ceramic substrate (TFC), a thick printing ceramic substrate (TPC), a direct bonded copper ceramic substrate (DBC), an active metal brazing ceramic substrate (AMB), a direct plated copper ceramic substrate (DPC), a laser activated metallization ceramic substrate (LAM), and the like. The connection pad 123 is arranged on the substrate to realize connection with an external PCB. The DBC direct bonded copper ceramic substrate is preferred in the utility model, which has low cost, good performance, and simple manufacturing process. The insulating plate 122 plays a role of insulation support in the substrate 120, and is made of a ceramic material with high insulation strength, high thermal conductivity, high temperature resistance, and corrosion resistance, such as aluminum oxide (Al2O3) and aluminum nitride (AlN).

[0037] The thickness of the protective layer 124 is 1-3 microns, and the protective layer 124 is a thin film with a thickness of 1-3 microns formed by drying a protective agent solution. The protective agent solution is an aqueous solution with a protective agent concentration of 85±10%. The protective agent is at least one of benzotriazole, imidazole organic crystalline base, triazole, and methyl benzotriazole. In the subsequent welding process for connecting with the external PCB, the organic protective layer is more easily volatilized when a certain temperature is reached.

[0038] A protective layer 124 is formed on the surface of the connection pad 123. On the one hand, the protective layer 124 can prevent oxidation of the part (pad) of the power module connected with the PCB, and can prevent the generation of welding cavities during welding connection of the power module and the PCB, thereby affecting the reliability of the power module. On the other hand, the protective layer 124 is beneficial to the storage of the power module after manufacturing, and is beneficial to mass production. In addition, the power module with the protective layer 124 has less impurities when connected with the PCB, and the connection with the PCB is more stable and less likely to fall off, thereby having more reliable performance.

[0039] The first metal layer 121 is used for arranging the circuit arrangement structure, and has an electrical gap for the circuit arrangement structure inside the shell 110, and the power chip 130 is welded on the first metal layer 121 inside the shell 110. In the embodiment, the first metal layer 121 is provided with four power chips arranged in an H-bridge circuit, and the power chip 130 can be a diode, a triode, a MOSFET, an IGBT, an FRD, an SIC, a GAN, etc. The first metal layer 121 serves as a support body, and the electrical connection between the chips and the electrical external connection path are built according to a certain circuit topology, and common circuit topologies can refer to single-tube, three-phase full-bridge, H-bridge, BUCK, BOOST, chopper circuit, etc. The power chip 130 is welded on the first metal layer 121, and the power chips are electrically connected through ultrasonic bonding of metal wires, and the power chip 130 is preferably arranged in the middle local area of the substrate 120.

[0040] The part of the first metal layer 121 outside the shell 110 is etched by a half-etching process to form a boss connected with the external PCB, i.e. a connection pad 123, and the connection pad 123 at least includes a control pad and a power pad.

[0041] The other surface of the insulating plate 122 is covered with a second metal layer 125, and the first metal layer 121 and the second metal layer 125 are respectively located on opposite surfaces of the insulating plate 122. The first metal layer 121 and the second metal layer 125 are both copper foil layers. The thickness of the second metal layer 125 can be selected according to different application requirements, so that the substrate 120 has a heat dissipation function.

[0042] Please refer to Figures 3-4 The application terminal further includes a PCB 200, the PCB 200 has a mounting hole 210 matched with the power module shell 110, the shell 110 penetrates the mounting hole 210, and the PCB 200 is welded with the connection pad 123. In addition, the application terminal further includes a heat sink 300, the heat sink 300 is fixedly connected with the PCB 200, and the second metal layer 125 faces the heat sink 300. The assembly process of the power module, the PCB and the heat sink is as follows:

[0043] The PCB 200 to be connected is placed horizontally, the shell 110 is inserted into the mounting hole 210 of the PCB 200, solder or soldering sheet is placed at the corresponding position where the pad of the PCB 200 is connected with the connecting pad 123 of the power module, then the soldering is performed in a reflow soldering furnace at 140-250 DEG C for 4-6 minutes, when soldering, the setting of the furnace temperature curve in the heating and cooling stages needs to be controlled to be lower than 2 DEG C / s, the gravity of the power module itself downward is used to strengthen the contact degree of the soldering of the solder / soldering sheet in the soldering process, the furnace temperature adjustment lower than 2 DEG C / s avoids the false soldering caused by stress, and the reliability of the terminal application is enhanced. The PCB 200 after soldering is inverted, so that the back of the power module is in contact with and connected with the external heat sink, the PCB 200 is provided with a pressing screw opening outside the power module, the heat sink is provided with a boss or stud conforming to the height of the bottom plate of the power module, the bolt 400 is used to make the bolt 400 pass through the pressing screw opening of the PCB and then be installed and fixed with the heat sink, and the assembly of the power module, the PCB 200 and the heat sink 300 is completed.

[0044] The above embodiments are only used to illustrate the technical solutions of the present application and not limit the present application, although the present application is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions of the present application, and all should be covered in the scope of the claims of the present application. The technical, shape and structure parts not described in detail in the present application are all known technologies.

Claims

1. A leadless semiconductor package power module, characterized by, The application relates to a pinless semiconductor integrated power module. The pinless semiconductor integrated power module comprises a shell, a substrate, a protective layer and a power chip. The substrate comprises an insulating plate and a first metal layer covering one surface of the insulating plate.

2. The leadless semiconductor power module of claim 1, wherein, The shell is encapsulated on the substrate, the first metal layer faces the shell, the first metal layer is provided with a connecting pad outside the shell, and the surface of the connecting pad is covered with the protective layer.

3. The leadless semiconductor power module of claim 1, wherein, The thickness of the protective layer is 1-3 microns.

4. The leadless semiconductor power module of claim 3, wherein, The first metal layer is used for arranging an electric circuit structure, the first metal layer inside the shell has an electric gap for the electric circuit structure, and the power chip is welded on the first metal layer inside the shell.

5. The leadless semiconductor power module of claim 1, wherein, The power chip is selected from at least one of a diode, a triode, a MOSFET, an IGBT, an FRD, an SIC and a GAN.

6. A leadless semiconductor power module according to claim 5, characterized in that The other surface of the insulating plate is covered with a second metal layer, and the first metal layer and the second metal layer are respectively located on opposite surfaces of the insulating plate.

7. A leadless semiconductor power module according to any one of claims 1 to 6, characterized in that The first metal layer and the second metal layer are both copper foil layers.

8. An application terminal, characterized by comprising: The shell is any one of an epoxy resin shell and a silicon gel shell.

9. The application terminal according to claim 8, wherein The application terminal comprises the pinless semiconductor integrated power module.

10. The application terminal of claim 9, wherein, The application terminal further comprises a PCB plate, the PCB plate is provided with a mounting hole, the shell penetrates through the mounting hole, and the PCB plate is welded with the connecting pad. The application terminal further comprises a heat sink, the heat sink is fixedly connected with the PCB plate, and the second metal layer faces the heat sink.

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