Novel hybrid vehicle power module

Abstract

The invention discloses a novel hybrid vehicle power module, and belongs to the technical field of power modules. Comprising an insulating ceramic substrate, and a conductive copper layer power circuit etching area is arranged on the insulating ceramic substrate; the silicon carbide chip is arranged in the power circuit etching region of the conductive copper layer through silver sintering; the power chip is arranged in the conductive copper layer power circuit etching region through silver sintering; the diode chip is arranged in the conductive copper layer power circuit etching region through silver sintering; and the bonding wires are respectively connected among the silicon carbide chip, the power chip, the diode chip and the conductive copper layer power circuit etching region. The beneficial effects of the technical scheme are that the silicon carbide chip, the power chip and the diode chip are packaged in a mixed manner, so that the silicon carbide characteristic is realized under a small-current working condition, the on-resistance is low under a large-current working condition, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power modules, and in particular to a vehicle power module. Background Art

[0002] In the current field of new energy vehicle technology, IGBT (Insulate-Gate Bipolar Transistor) power modules and SiC (Silicon Carbide) power modules have become core components and are widely used. With its mature technology and relatively stable performance, IGBT power modules play a key role in the motor control systems and charging systems of many new energy vehicles. SiC power modules, with their excellent material properties, show unique advantages in high-voltage and high-frequency working scenarios, and can significantly improve the power density and system efficiency of new energy vehicles.

[0003] However, the existing IGBT power modules and SiC power modules still have a lot of room for improvement in on-resistance. Higher on-resistance means more energy loss when current passes through the power module. These losses are dissipated in the form of heat, which not only reduces the energy conversion efficiency, but also increases the burden on the heat dissipation system. In addition, both IGBT power modules and SiC power modules have high manufacturing costs, resulting in high overall costs for new energy vehicles. Summary of the invention

[0004] The purpose of the present invention is to provide a new hybrid vehicle power module to solve the above technical problems;

[0005] A novel hybrid vehicle power module, comprising:

[0006] An insulating ceramic substrate, wherein a conductive copper layer power circuit etching area is provided on the insulating ceramic substrate;

[0007] A silicon carbide chip is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering;

[0008] A power chip is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering;

[0009] A diode chip is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering;

[0010] Bonding wires are respectively connected between the silicon carbide chip, the power chip, the diode chip and the conductive copper layer power circuit etching area.

[0011] Preferably, a silver sintering layer is provided between the silicon carbide chip and the conductive copper layer power circuit etching area;

[0012] The silver sintering layer is provided between the power chip and the conductive copper layer power circuit etching area;

[0013] The silver sintering layer is provided between the diode chip and the conductive copper layer power circuit etching area;

[0014] The silver sintered layer includes one of a silver paste and a silver film;

[0015] The sintering temperature of the silver sintering layer is 200° C. to 400° C., and the sintering pressure of the silver sintering layer is 5 MPa to 50 MPa.

[0016] Preferably, the outer surfaces of the silicon carbide chip, the power chip and the diode chip are all provided with a metal layer;

[0017] The metal layer includes one of Ni / Pd / Au, Al / Ti / NiV / Ag, and Al / NiV / Ag.

[0018] Preferably, the bonding wire comprises one of a copper wire, an aluminum wire, and an aluminum-clad copper wire;

[0019] The diameter of the bonding wire includes one of 8 mil, 12 mil, 16 mil, and 20 mil.

[0020] Preferably, the back side of the insulating ceramic substrate is connected to a heat dissipating copper substrate by soldering or silver sintering.

[0021] Preferably, it also includes:

[0022] An injection molded housing with an ultrasonically welded power terminal is ultrasonically welded to the outer side of the insulating ceramic substrate. An accommodating area is provided between the injection molded housing and the insulating ceramic substrate. The accommodating area is provided with:

[0023] The silicon carbide chip, the power chip, the diode chip and the bonding wire.

[0024] Preferably, an upper cover is provided above the injection-molded housing.

[0025] Preferably, a sealant is provided between the injection-molded housing and the heat dissipation copper substrate.

[0026] Preferably, a pin-fin structure for water cooling is provided on the back side of the heat dissipation copper substrate.

[0027] Preferably, the accommodating area is further provided with:

[0028] A copper signal terminal is soldered or ultrasonically welded to the insulating ceramic substrate;

[0029] A bonding resistor is provided on the insulating ceramic substrate;

[0030] The thermistor is arranged on the insulating ceramic substrate.

[0031] The beneficial effect of the present invention is that by hybrid packaging of silicon carbide chips, power chips and diode chips, the silicon carbide characteristics are achieved under low current conditions, and the on-resistance is low under high current conditions, thereby reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the overall structure of three new hybrid vehicle power modules connected in the present invention;

[0033] Figure 2 It is a schematic diagram of the internal structure of three novel hybrid vehicle power modules connected in the present invention;

[0034] Figure 3 yes Figure 2 A partial enlarged view of the M in the middle;

[0035] Figure 4 It is a schematic diagram of the circuit structure of a novel hybrid vehicle power module of the present invention;

[0036] Figure 5 It is a circuit structure schematic diagram of the thermistor of the present invention.

[0037] In the attached figure: 1. Insulating ceramic substrate; 2. Silicon carbide chip; 3. Power chip; 4. Diode chip; 5. Bonding wire; 6. Heat dissipation copper substrate; 7. Injection molded shell; 8. Upper cover; 9. Copper signal terminal; 10. Bonding resistor; 11. Thermistor. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0039] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0040] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0041] A new hybrid vehicle power module, such as Figure 1 , Figure 2 As shown, including,

[0042] An insulating ceramic substrate 1, on which a conductive copper layer power circuit etching area is provided;

[0043] The silicon carbide chip 2 is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering;

[0044] The power chip 3 is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering;

[0045] The diode chip 4 is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering;

[0046] The bonding wires 5 are respectively connected between the silicon carbide chip 2, the power chip 3, the diode chip 4 and the conductive copper layer power circuit etching area.

[0047] Specifically, the present invention provides a novel hybrid automotive power module, including a silicon carbide chip 2 (SiC MOSFET) that can be silver-sintered on both sides, a power chip 3 (IGBT) that can be sintered on the back side, and a diode chip 4 that can be sintered on the back side. The silicon carbide chip 2, the power chip 3 and the diode chip 4 are mixed and packaged to achieve the characteristics of silicon carbide under low current conditions and low on-resistance under high current conditions, thereby reducing costs.

[0048] The insulating ceramic substrate 1 may be a Si3N4 (silicon nitride) insulating ceramic substrate AMB (Active Metal Brazing), which is a process used in preparing a ceramic substrate.

[0049] Through this process, an active metal brazing layer, usually a copper layer, is formed on the surface of the Si3N4 ceramic.

[0050] The copper layer can be better connected to components such as chips, for example, through silver sintering, etc., to achieve good electrical connection and heat conduction between the chip and the substrate, and has higher reliability and stability.

[0051] The insulating ceramic substrate 1 may also be DBC (Direct Bonded Copper). DBC is a technology for directly bonding copper foil to a ceramic substrate.

[0052] The ceramic substrate material can be a variety of ceramic materials such as alumina.

[0053] The advantages of DBC substrates are: good thermal cycle performance, can effectively resist thermal stress during repeated heating and cooling of the power module, and reduce problems such as delamination and cracking caused by mismatched thermal expansion coefficients.

[0054] In power modules, DBC substrates can be used as a chip carrier platform and connected to the chip through a suitable bonding process (such as soldering, etc.). Its good heat dissipation and electrical performance can ensure the stable operation of the chip under high-power working conditions, and due to its mature preparation process and relatively low cost, it has certain advantages in some power module application scenarios that are more cost-sensitive or have slightly lower performance requirements.

[0055] Reference Figure 2 , a module has Figure 4 The three bridge arms shown in the figure each include two silicon carbide chips 2 and two power chips 3. A module includes an upper tube and a lower tube. An upper tube or a lower tube adopts the following Figure 4 The three diode chips 4 shown are connected in anti-parallel for freewheeling.

[0056] The power chip 3 and the silicon carbide chip 2 use a common C pole ( Figure 2 C) and the common E pole ( Figure 2 E in the figure, G pole of power chip 3 ( Figure 2 IGBT-G in the silicon carbide chip 2) and the G pole ( Figure 2 SiC-G) in the circuit uses independent signal lead-out.

[0057] There are bonding points on the chip surface of the bonding area. One end of the bonding wire 5 is bonded to the insulating ceramic substrate 1, and the middle part is bonded to the chip. There are two bonding points on each IGBT chip, and there is one bonding point on the SiC chip and the diode chip 4, and the other end is bonded to the insulating ceramic substrate 1.

[0058] In a preferred embodiment, a silver sintering layer is provided between the silicon carbide chip 2 and the conductive copper layer power circuit etching area;

[0059] A silver sintering layer is provided between the power chip 3 and the conductive copper layer power circuit etching area;

[0060] A silver sintering layer is provided between the diode chip 4 and the conductive copper layer power circuit etching area;

[0061] The silver sintering layer includes one of a silver paste and a silver film;

[0062] The sintering temperature of the silver sintering layer is 200° C. to 400° C., and the sintering pressure of the silver sintering layer is 5 MPa to 50 MPa.

[0063] Specifically, by connecting the chip with the conductive copper layer power circuit etching area through the silver sintering layer, a low-resistance, high-reliability electrical connection between the chip and the circuit can be achieved, which can effectively reduce the contact resistance and reduce the loss during signal transmission, ensuring that the power module can efficiently perform power conversion and signal transmission under various working conditions.

[0064] Silver is an excellent conductive material. When silver paste or silver film is used as the silver sintering layer material, during the sintering process, the solvent in the silver paste evaporates, and the silver particles fuse with each other under high temperature and pressure, or the silver film fits tightly with the chip and the conductive copper layer under high temperature and pressure to form a continuous conductive channel. This tight connection allows electrons to flow smoothly between the chip and the circuit, thus ensuring a good electrical connection.

[0065] The silver sintered layer helps the heat generated by the chip when it is working to be quickly transferred to the conductive copper layer power circuit etching area, and then dissipated through the substrate and other heat dissipation channels. This can effectively prevent the chip from performance degradation or damage due to overheating, and improve the reliability and service life of the power module.

[0066] Silver not only has good electrical conductivity, but also high thermal conductivity. The silver sintered layer tightly connects the chip and the conductive copper layer. The heat generated by the chip can be quickly transferred to the conductive copper layer through the silver sintered layer.

[0067] The basic principle of heat conduction is that heat is transferred from the high-temperature area (chip) to the low-temperature area (conductive copper layer). The silver sintered layer serves as the intermediate heat conduction medium. Its high thermal conductivity can accelerate this process, allowing heat to be dissipated quickly and maintain the normal working temperature of the chip.

[0068] The sintering temperature of the silver sintering layer is specified to be 200℃~400℃, and the sintering pressure is 5Mpa~50Mpa. The clear process parameter range enables more precise control of the manufacturing process, helps improve the consistency of product quality, ensures that the performance of each power module meets the expected standards, and facilitates large-scale production.

[0069] Within the above temperature and pressure ranges, the silver paste or silver film can undergo appropriate physical changes to form an ideal sintered layer.

[0070] If the temperature is too low or the pressure is insufficient, the silver particles may not fuse sufficiently or the silver film may not adhere tightly, resulting in poor quality of the sintered layer.

[0071] However, excessive temperature or pressure may damage the chip and substrate, or cause over-sintering of the silver layer, such as deformation of the silver layer and decreased adhesion to the chip or substrate.

[0072] The silver sintering connection method can reduce costs to a certain extent by properly selecting silver paste or silver film materials and controlling the sintering process while ensuring good performance. Compared with some other connection methods or materials, the use of silver sintering layers can optimize the cost structure while meeting performance requirements.

[0073] Silver paste and silver film materials are relatively easy to obtain and process, and can effectively connect the chip and the conductive copper layer under the appropriate sintering temperature and pressure. Compared with some complex or expensive connection technologies, the cost of the silver sintering process is relatively low, and through mass production and optimization of process parameters, the unit cost can be further reduced, thereby reducing the cost while ensuring the high performance of the power module.

[0074] In a preferred embodiment, the outer surfaces of the silicon carbide chip 2, the power chip 3 and the diode chip 4 are all provided with a metal layer;

[0075] The metal layer includes one of Ni / Pd / Au, Al / Ti / NiV / Ag, and Al / NiV / Ag.

[0076] Specifically, taking the Ni / Pd / Au metal layer as an example, the nickel (Ni) layer can enhance the adhesion between the metal layer and the chip surface, providing a good adhesion foundation for the subsequent palladium (Pd) and gold (Au) layers.

[0077] The palladium layer can improve the chemical stability of the metal surface, making it less susceptible to chemical reactions such as oxidation during subsequent welding or bonding processes, thereby ensuring good solderability.

[0078] The gold layer itself has excellent conductivity and chemical stability, and can form good intermetallic compounds with commonly used bonding wire materials (such as gold wire, aluminum wire, etc.), which is conducive to the smooth progress of the bonding process and the realization of a firm connection.

[0079] For the two metal layer combinations of Al / Ti / NiV / Ag and Al / NiV / Ag, the aluminum (Al) layer can be used to form a good initial contact interface with the chip surface.

[0080] The titanium (Ti) layer can improve the bonding strength between the metal layer and the chip, and act as a barrier layer to prevent excessive diffusion of other elements that would affect connection performance.

[0081] The nickel-vanadium alloy (NiV) layer can adjust the physical and chemical properties of the metal layer, such as hardness, thermal stability, etc., to adapt it to different process conditions.

[0082] The silver (Ag) layer further improves the electrical and thermal performance of the connection parts due to its good electrical and thermal conductivity, making it easier to connect with other components later.

[0083] In the complex environment where automotive power modules are located (which may be exposed to moisture, dust, oil, and corrosion from various chemicals, etc.), the metal layer on the outer surface of the chip can play a protective role, effectively blocking external corrosive substances from contacting the chip, slowing down the corrosion rate of the chip, and extending the service life of the chip, thereby improving the durability and reliability of the entire power module.

[0084] Among the metal layers mentioned above, metals such as gold (Au), palladium (Pd), and silver (Ag) are relatively stable in chemical properties and are not easy to react chemically with common corrosive substances (such as oxygen, moisture, acidic or alkaline substances, etc.).

[0085] Even during long-term use, these metal layers will first come into contact with the external environment, and rely on their own corrosion resistance to build a protective barrier for the chip surface, protecting the semiconductor materials and circuit structures inside the chip from corrosion and maintaining the normal electrical performance and functions of the chip.

[0086] Since metals generally have good thermal conductivity, the metal layer on the outer surface of the chip can serve as an auxiliary heat dissipation channel, helping the chip to transfer heat more efficiently during operation, avoiding performance degradation, accelerated aging, or even damage of the chip due to overheating, and ensuring the stability and reliability of the power module under high-power operating conditions.

[0087] Metals such as silver (Ag) and aluminum (Al) have high thermal conductivity in the metal layer combination. The heat generated by the chip can be conducted through these metal layers to the surrounding environment or to heat dissipation components connected to the chip (such as insulating ceramic substrates, etc.).

[0088] It can adjust the electrical properties of the chip surface, such as reducing the contact resistance when the chip is connected to the outside, improving the current transmission efficiency, and reducing the loss of electric energy during the transmission process, thereby improving the energy conversion efficiency of the entire power module and better meeting the requirements of automotive power modules for efficient power processing.

[0089] The various metal elements in the metal layer work together according to their own conductive properties.

[0090] For example, gold (Au) and silver (Ag) have very low resistivity and can form a low-resistance conductive path on the chip surface, making the current flow in and out of the chip smoother, reducing the Joule heat and power loss caused by contact resistance.

[0091] At the same time, the reasonable combination of metal layers (such as through the role of blocking layers, regulating layers, etc.) can optimize the transmission behavior of electrons and further improve the overall electrical performance of the chip.

[0092] In a preferred embodiment, the bonding wire 5 includes one of a copper wire, an aluminum wire, and an aluminum-clad copper wire;

[0093] The diameter of the bonding wire 5 includes one of 8 mil, 12 mil, 16 mil, and 20 mil.

[0094] Specifically, the present invention is applicable to a range of chips including silicon-based MOSFET chips, silicon-based IGBT chips, SiC chips or GaN chips, and diode chips 4 .

[0095] The 8mil diameter is suitable for small current and fine circuit connections. In the power module, for some small current transmission paths or circuit connection parts that require fine spatial layout, the 8mil diameter bonding wire 5 is relatively thin, which can achieve more precise connection and avoid space occupation problems caused by excessively thick wire diameters. At the same time, it can also meet the stable current transmission requirements under small current conditions. In some scenarios with high requirements for signal transmission accuracy, thinner bonding wires 5 help reduce signal interference.

[0096] It helps to achieve the miniaturization of power modules. For automotive power modules, smaller size can be more flexibly arranged within the limited space of the vehicle, which is in line with the trend of continuous miniaturization and integration of automotive electronic systems.

[0097] A thinner bonding wire means a smaller cross-sectional area. In the case of low current, based on the relationship between current and resistance (resistance is inversely proportional to cross-sectional area), its own resistance will be relatively higher, but it has little effect on low current transmission and can still ensure normal signal transmission. In terms of spatial layout, thin bonding wires are easier to route in a small space, achieving a more compact circuit design.

[0098] The bonding wires 5 with diameters of 12mil, 16mil, and 20mil are suitable for large current transmission. As the wire diameter increases, the cross-sectional area of ​​the bonding wire increases accordingly. According to the resistance law, its resistance decreases.

[0099] When the power module handles large currents, the bonding wires 5 with diameters of 12mil, 16mil, and 20mil can carry larger currents, reduce the heat generated by the current passing through the bonding wires 5 (Joule heat is proportional to the square of the current and the resistance), and avoid overheating of the bonding wires 5, thereby ensuring the reliability and stability of the electrical connection under high current conditions, and also helping to improve the working efficiency and performance of the entire power module.

[0100] The relatively thick wire diameter makes the bonding wire 5 itself have better mechanical strength, and is less likely to break or loosen when facing external forces such as vibration and impact during vehicle driving, further ensuring long-term and stable connection between the chip and the circuit and reducing the occurrence of failures.

[0101] The present invention realizes electrical interconnection by bonding aluminum wires, copper wires or aluminum-clad copper wires as leads to connect with the chip and the insulating ceramic substrate 1 .

[0102] The bonding aluminum wire, copper wire or aluminum-clad copper wire is bonded to the chip and the surface of the insulating ceramic substrate 1 respectively through ultrasonic welding process. There are at least 1 to 2 bonding points on each chip, and the bonding method is evenly distributed side by side.

[0103] The back of the chip uses a silver sintering connection process, which has excellent electrical and thermal conductivity, and the power cycle capacity of the module is greatly improved.

[0104] The front of the chip adopts aluminum wire, copper wire or aluminum-clad copper wire binding technology. The new hybrid automotive power module can maximize the benefits by mixed packaging of silicon carbide chip 2, power chip 3 and diode chip 4. It has SiC characteristics under small current and low on-resistance under large current.

[0105] Aluminum copper wire is made of aluminum wrapped around the outer layer of copper core wire. It has the good conductivity and ductility of copper wire, as well as the lighter weight and lower cost of aluminum wire. Its wire diameter includes but is not limited to 8mil, 12mil, 16mil, and 20mil.

[0106] The structure of the insulating ceramic substrate 1 is a copper layer structure with upper and lower layers made of oxygen-free copper, and the middle layer is a ceramic material layer made of Si3N4 with high thermal conductivity and high reliability. Its product process is to sinter and combine the copper layer and the ceramic layer through a sintering process.

[0107] In a preferred embodiment, the back side of the insulating ceramic substrate 1 is connected to a heat dissipating copper substrate 6 by soldering or silver sintering.

[0108] The silicon carbide chip 2, the power chip 3, and the diode chip 4 are welded on the insulating ceramic substrate 1 through welding materials, and the insulating ceramic substrate 1 is welded on the heat dissipation copper substrate 6 through welding materials to be packaged into a complete power module.

[0109] In a preferred embodiment, it also includes:

[0110] The injection molded housing 7 with ultrasonically welded power terminals is ultrasonically welded to the outer side of the insulating ceramic substrate 1. An accommodating area is provided between the injection molded housing 7 and the insulating ceramic substrate 1. The accommodating area is provided with:

[0111] Silicon carbide chip 2 , power chip 3 , diode chip 4 and bonding wire 5 .

[0112] Specifically, the injection molded housing 7 is provided with ultrasonically welded power terminals, making the integration and installation of the power module in the vehicle electrical system more convenient.

[0113] Ultrasonic welded power terminals can be directly connected to other electrical components of the vehicle without complicated additional wiring operations, reducing the workload and possibility of errors during installation.

[0114] After the entire power module is encapsulated by the injection molded housing 7, an independent, easy-to-operate unit is formed, which is convenient for overall installation and disassembly in the layout of automotive electronic equipment, and is conducive to maintenance and replacement.

[0115] In a preferred embodiment, an upper cover 8 is provided above the injection molded housing 7;

[0116] A sealant is provided between the injection-molded housing 7 and the heat-dissipating copper substrate 6 .

[0117] Specifically, the vehicle power module of the present invention is packaged using high-temperature sealant, high-temperature silicone and a plastic upper cover 8 .

[0118] An upper cover 8 is arranged above the injection molded housing 7 and is sealed with a sealant, which can further enhance the protection of the internal components (silicon carbide chip 2, power chip 3, diode chip 4 and bonding wire 5).

[0119] The multi-layer protection structure can effectively prevent external dust, moisture, oil and other impurities from entering the power module.

[0120] The use of high-temperature sealant and high-temperature silicone for packaging enables the power module to adapt to high-temperature environments such as automobile engine compartments.

[0121] During vehicle operation, especially near the engine or when running at high power, the temperature around the power module will rise significantly. High temperature sealants and high temperature silicone can maintain their sealing performance and physical and chemical properties under high temperature conditions, ensuring the normal operation of internal components and preventing components from being exposed to high temperature environments due to failure of sealing materials.

[0122] In a preferred embodiment, a pin-fin structure for water cooling is provided on the back side of the heat dissipation copper substrate 6 .

[0123] Specifically, the heat dissipation copper substrate 6 with pinfin (pin fin structure) is in contact with the coolant through the pinfin structure to perform water cooling and heat dissipation.

[0124] The pin-fin structure can increase the contact area between the heat dissipating copper substrate 6 and the coolant, so that heat can be transferred from the copper substrate to the coolant more quickly, effectively reducing the temperature of the power module, thereby ensuring that the chip operates within an appropriate operating temperature range and avoiding performance degradation or damage due to overheating.

[0125] The ultrasonically welded power terminals on the injection molded housing 7 can be connected to external devices for circuit connection.

[0126] Specifically, the ultrasonically welded power terminals serve as a standardized connection interface, making it easier to maintain and replace the power module when it fails or needs to be upgraded.

[0127] In a preferred embodiment, referring to Figure 2 , Figure 3 , Figure 5 , the accommodation area is also equipped with

[0128] The copper signal terminal 9 is soldered or ultrasonically welded on the insulating ceramic substrate 1;

[0129] The bonding resistor 10 is provided on the insulating ceramic substrate 1;

[0130] The thermistor 11 is disposed on the insulating ceramic substrate 1 . The thermistor 11 is disposed between two adjacent copper signal terminals 9 .

[0131] Specifically, the soft soldering fills the gap between the copper signal terminal 9 and the insulating ceramic substrate 1 with molten solder, and forms a firm connection after cooling. This connection method can ensure good electrical contact.

[0132] Ultrasonic welding uses high-frequency vibrations to cause the metal atoms between the terminal and the substrate to diffuse into each other, forming a metallurgical bond, thereby achieving a low-resistance, high-reliability connection.

[0133] Copper itself has good conductivity because it contains a large number of free electrons. These free electrons can move in a directed manner under the action of an electric field, thereby achieving efficient signal transmission.

[0134] The bonding resistor 10 is disposed on the insulating ceramic substrate 1 and can play a role in regulating current and voltage in the circuit of the power module.

[0135] For example, in some circuits that require precise control of power output, by appropriately selecting the resistance value of the bonding resistor 10, the current size can be controlled, thereby achieving the purpose of adjusting the output power of the power module and meeting the power requirements of the car under different working conditions.

[0136] In the signal transmission circuit, the bonding resistor 10 can also be used for signal attenuation or matching, and can adjust the amplitude of the signal to better match the input and output signals in terms of amplitude, frequency, etc., reduce signal reflection and distortion, improve the quality of signal transmission, and ensure the communication quality between the power module and other electronic devices.

[0137] When the voltage is constant, changing the resistance value of the resistor can adjust the current passing through the circuit. In the circuit design of the power module, the resistance value of the bonding resistor 10 can be reasonably used to accurately control the current in the circuit.

[0138] For signal transmission, the bonding resistor 10 can be used as a terminal matching resistor. When the characteristic impedance of the transmission line matches the resistance value of the bonding resistor 10, the reflection of the signal during transmission can be minimized to ensure the integrity of the signal.

[0139] The thermistor 11 is arranged between two adjacent copper signal terminals 9, and can monitor the temperature inside the power module in real time. Due to the complex operating environment of the automobile, the power module may have an overheated temperature during operation due to overload, poor heat dissipation, etc.

[0140] The thermistor 11 can sense temperature changes in time. When the temperature exceeds a safety threshold, a protection mechanism can be triggered, such as sending an alarm signal to the vehicle electronic control system or automatically adjusting the working state of the power module to prevent key components such as chips from being damaged due to overheating.

[0141] In the circuit of the power module, temperature changes may affect the performance of other electronic components, such as causing changes in resistance values, changes in transistor characteristics, etc. The thermistor 11 can be used for temperature compensation. By cooperating with other components, the circuit parameters are automatically adjusted according to temperature changes to ensure that the entire power module can maintain stable performance under different temperature environments.

[0142] The copper signal terminal 9 is connected to the Si3N4 insulating ceramic substrate AMB by soldering or ultrasonic welding, and the other end of the signal terminal can be connected to the external structural circuit board for circuit connection.

[0143] The signal pole of the silicon carbide chip 2 which can be silver-sintered on both sides and the power chip 3 which can be sintered on the back side are electrically connected to the signal and control circuit in the signal circuit etching area of ​​the Si3N4 insulating ceramic substrate AMB conductive copper layer through aluminum wire or aluminum-copper wire binding process, which can maximize the benefits, have SiC characteristics under small current, and have low on-resistance under large current.

[0144] The back of the silicon carbide chip 2, the power chip 3, and the diode chip 4 are connected to the Si3N4 insulating ceramic substrate AMB using a silver sintering process. Compared with the traditional soft soldering connection process, the silver sintering connection material has a melting point above 900°C, which greatly improves the operating temperature. Due to its own material properties, it has high reliability characteristics with strong resistance to temperature cycling, thereby improving the power cycling and temperature cycling capabilities of the module.

[0145] The new hybrid vehicle power module can maximize benefits by mixed packaging of SiC MOSFET chips, IGBT chips, and diode chips. It has SiC characteristics under low current and low on-resistance under high current.

[0146] The front side of the SiC MOSFET chip, IGBT chip, and diode chip 4 are connected to the Si3N4 insulating ceramic substrate AMB conductive copper layer power circuit etching area using aluminum wire or aluminum-copper wire bonding technology; compared with the chip front side sintering process and copper foil and copper wire bonding technology, the aluminum wire or aluminum-copper wire bonding process is used for electrical connection, which can be directly bonded to the front side of the chip, reducing the sintering process steps and improving packaging efficiency.

[0147] Moreover, aluminum-copper wire has the good conductivity and ductility of copper wire, and the lighter weight and lower cost of aluminum wire.

[0148] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel hybrid vehicle power module, characterized in that: include, An insulating ceramic substrate, wherein a conductive copper layer power circuit etching area is provided on the insulating ceramic substrate; A silicon carbide chip is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering; A power chip is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering; A diode chip is arranged in the power circuit etching area of ​​the conductive copper layer by silver sintering; Bonding wires are respectively connected between the silicon carbide chip, the power chip, the diode chip and the conductive copper layer power circuit etching area.

2. The novel hybrid vehicle power module according to claim 1, characterized in that: A silver sintering layer is provided between the silicon carbide chip and the conductive copper layer power circuit etching area; The silver sintering layer is provided between the power chip and the conductive copper layer power circuit etching area; The silver sintering layer is provided between the diode chip and the conductive copper layer power circuit etching area; The silver sintered layer includes one of a silver paste and a silver film; The sintering temperature of the silver sintering layer is 200° C. to 400° C., and the sintering pressure of the silver sintering layer is 5 MPa to 50 MPa.

3. The novel hybrid vehicle power module according to claim 1, characterized in that: The outer surfaces of the silicon carbide chip, the power chip and the diode chip are all provided with a metal layer; The metal layer includes one of Ni / Pd / Au, Al / Ti / NiV / Ag, and Al / NiV / Ag.

4. The novel hybrid vehicle power module according to claim 1, characterized in that: The bonding wire includes one of a copper wire, an aluminum wire, and an aluminum-clad copper wire; The diameter of the bonding wire includes one of 8 mil, 12 mil, 16 mil, and 20 mil.

5. The novel hybrid vehicle power module according to claim 1, characterized in that: The back side of the insulating ceramic substrate is connected to a heat dissipation copper substrate by soldering or silver sintering.

6. The novel hybrid vehicle power module according to claim 5, characterized in that: Also includes, An injection molded housing with an ultrasonically welded power terminal is ultrasonically welded to the outer side of the insulating ceramic substrate. An accommodating area is provided between the injection molded housing and the insulating ceramic substrate. The accommodating area is provided with: The silicon carbide chip, the power chip, the diode chip and the bonding wire.

7. The novel hybrid vehicle power module according to claim 6, characterized in that: An upper cover is arranged above the injection molded shell.

8. The novel hybrid vehicle power module according to claim 6, characterized in that: A sealant is provided between the injection-molded housing and the heat-dissipating copper substrate.

9. The novel hybrid vehicle power module according to claim 5, characterized in that: The back side of the heat dissipation copper substrate is provided with a pin fin structure for water cooling and heat dissipation.

10. The novel hybrid vehicle power module according to claim 6, characterized in that: The accommodation area is also provided with: A copper signal terminal is soldered or ultrasonically welded to the insulating ceramic substrate; A bonding resistor is provided on the insulating ceramic substrate; The thermistor is arranged on the insulating ceramic substrate.

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