IGBT device based on PMOS tube and preparation method thereof

Abstract

The present invention discloses an IGBT device based on a PMOS tube and a preparation method thereof, the method comprising the following steps: providing a packaging frame; compounding an IGBT chip onto the packaging frame through a DAF process; S3. applying glue on the surface of the IGBT chip; compounding a PMOS wafer onto the IGBT chip through a DAF process; bonding the PMOS drain to the IGBT gate, and bonding the PMOS gate, the IGBT emitter, and the PMOS source to each pin of the packaging frame respectively; wherein the pin of the packaging frame bonded to the PMOS source is constructed to be suitable for connecting to a driver IC of the IGBT device. The IGBT device based on the PMOS tube is prepared by the above method. The transient current change when the IGBT is started is effectively reduced, and EMI is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of IGBT devices, and in particular to a method for preparing an IGBT device based on a PMOS tube and an IGBT device based on a PMOS tube prepared by the preparation method. Background Art

[0002] IGBT refers to Insulated Gate Bipolar Transistor, which is a semiconductor device that combines the advantages of field effect transistor (FET) and bipolar transistor (BJT). The structure of IGBT is similar to a combination of a MOSFET and a BJT. There is a P+ layer on the N-type substrate to form a PNP structure, and then a MOSFET structure is built on it. IGBT devices are usually used in a variety of high-voltage and high-current applications such as motors, inverters, PFC, etc. IGBT plays a vital role in the field of power electronics and motor control. It provides efficient power conversion and control capabilities, especially in high-power applications. With the development of technology, IGBT is also constantly improving to improve its performance, reduce switching losses and enhance heat resistance. The electromagnetic waves generated by semiconductor devices such as IGBT during operation may cause interference to other electronic devices or systems, namely EMI (electromagnetic interference). This interference can be conductive (conducted through wires or circuits) or radiative (transmitted through the air). Therefore, controlling and reducing EMI is an important topic. In the field of IGBT, large EMI (electromagnetic interference) can lead to many defects, such as signal interference, increased power loss, reduced reliability, electromagnetic compatibility issues, noise, interference in the control system, voltage spikes and overvoltage. The main reason for poor EMI is the rapid change of current during the IGBT switching process, that is, the di / dt (instantaneous current change) is too large. Therefore, it is urgent to improve the existing IGBT device preparation process to solve the problem of large EMI generated during the IGBT switching process. Summary of the invention

[0003] In order to solve the above technical problems, the purpose of the present invention is to provide an IGBT device based on a PMOS tube and a preparation method thereof, so as to prepare an IGBT device based on a PMOS tube and reduce the electromagnetic interference generated during the IGBT switching process.

[0004] To this end, on the one hand, the present invention provides a method for preparing an IGBT device based on a PMOS tube, comprising the following steps: S1. providing a packaging frame; S2. compounding an IGBT chip onto the packaging frame through a DAF process; S3. applying glue on the surface of the IGBT chip; S4. compounding a PMOS wafer onto the IGBT chip through a DAF process; S5. bonding the PMOS drain to the IGBT gate, and bonding the PMOS gate, the IGBT emitter, and the PMOS source to each pin of the packaging frame respectively; wherein the pin of the packaging frame bonded to the PMOS source is constructed to be suitable for connecting to a driver IC of the IGBT device.

[0005] According to an embodiment of the present invention, the constituent material of the packaging frame includes one of copper, nickel-iron alloy, aluminum, beryllium-copper alloy, and titanium alloy, or a combination of any two or more of them.

[0006] According to an embodiment of the present invention, in step S2 and step S4, the DAF process steps include: selecting a DAF film, preparing a DAF film, bonding the DAF film, placing an IGBT chip or a PMOS wafer, and baking.

[0007] According to an embodiment of the present invention, in the step of selecting the DAF film, the material of the DAF film includes one or a combination of epoxy resin, polyimide, polyimide, polyester, polystyrene, polycarbonate, polyurethane, and acrylic resin.

[0008] According to an embodiment of the present invention, in the step of preparing the DAF film, the DAF film is pre-cut into segments matching the size of the IGBT chip or the size of the PMOS wafer.

[0009] According to an embodiment of the present invention, the baking temperature is between 100° C. and 150° C., the baking pressure is between 0.1 MPa and 1 MPa, and the baking time is between 3 min and 20 min.

[0010] According to an embodiment of the present invention, in step S3, the step of applying glue on the surface of the IGBT chip includes: selecting glue, cleaning the surface of the IGBT, applying glue on the surface of the IGBT, and curing.

[0011] According to one embodiment of the present invention, the glue is one of XYC-FF06 glue, epoxy resin glue, silicone glue, hot melt glue, polyurethane glue, and polyimide glue.

[0012] According to an embodiment of the present invention, in step S5, the metal wire used in the bonding step includes one of aluminum wire, gold wire, copper wire, silver wire, platinum wire, nickel wire, silver alloy wire, and copper alloy wire.

[0013] According to an embodiment of the present invention, in the step S5, the steps of inspection and annealing are further included after the bonding step.

[0014] On the other hand, the present invention further provides an IGBT device based on a PMOS tube, which is prepared by using any of the preparation methods described in the above technical solutions.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The DAF process effectively reduces transient current changes during IGBT startup and reduces EMI by providing advantages such as high precision, low stress, simplified process flow, and reduced pollution. It is suitable for a variety of packaging forms and has high adaptability and environmental protection. Although the initial cost of the DAF film may be high, the overall production cost can be reduced by improving production efficiency and reducing material waste.

[0017] By bonding the PMOS drain to the IGBT gate and connecting the PMOS source to the driver IC of the IGBT device, when di / dt (instantaneous current change) is large during the IGBT switching process, a PMOS tube is set between the IGBT driver IC and the IGBT gate, and its threshold voltage is set to about 4V. When the di / dt generated by the IGBT device switch is large, the IGBT emitter stray inductance will produce a voltage drop, which will increase the on-state voltage drop of the PMOS, thereby increasing the RDSON (on-state resistance) of the PMOS itself. The increase in RDSON will increase the gate drive resistance, reduce the IGBT drive current, reduce the IGBT turn-on speed, and thus reduce di / dt to improve EMI.

[0018] It can ensure the stable operation of equipment, make the electronic system more stable, extend the product life and improve the product market competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a flowchart of a method for preparing an IGBT device based on a PMOS tube according to an embodiment of the present invention.

[0020] Figure 2 yes Figure 1 The figure shows a schematic diagram of the structure in which the IGBT chip and the PMOS wafer are respectively compounded by the DAF process.

[0021] Figure 3 Is adopted Figure 1 Schematic diagram of the structure of an IGBT device based on a PMOS tube prepared by the preparation method shown in .

[0022] Figure 4It is a connection structure diagram between an IGBT chip and a PMOS wafer of an IGBT device based on a PMOS tube according to an embodiment of the present invention.

[0023] Figure 5 It is an equivalent circuit diagram of an IGBT device based on a PMOS tube according to an embodiment of the present invention.

[0024] The reference numerals are as follows:

[0025] 10. Packaging frame;

[0026] 20. IGBT chip; 21. IGBT emitter; 22. IGBT gate;

[0027] 30. PMOS wafer; 31. PMOS drain; 32. PMOS gate; 33. PMOS source;

[0028] 40. Driver IC. DETAILED DESCRIPTION

[0029] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction to the technical solution of the present invention.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the directions or positional relationships indicated by terms such as center, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, etc. are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0031] In the description of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms first and second are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as first and second may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, the meaning of multiple is two or more.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms installation, connection, and connection should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] according to Figure 1 , Figure 2 As shown, an embodiment of the present invention provides a method for preparing an IGBT device based on a PMOS tube, and the process steps are as follows: S1. Provide a packaging frame 10; S2. Composite the IGBT chip 20 onto the packaging frame 10 through a DAF process; S3. Apply glue on the surface of the IGBT chip 20; S4. Composite the PMOS wafer 30 onto the IGBT chip 20 through a DAF process; S5. Bond the PMOS drain 31 to the IGBT gate 22, and bond the PMOS gate 32, the IGBT emitter 21, and the PMOS source 33 to each pin of the packaging frame 10 respectively; wherein, the pin of the packaging frame 10 bonded to the PMOS source 33 is constructed to be suitable for connecting to the driver IC 40 of the IGBT device.

[0034] Specifically, in step S1, firstly, a suitable packaging frame material is selected, such as copper or nickel-iron alloy (such as Kovar), to ensure that the frame has good conductivity and mechanical strength. In some embodiments, the material constituting the packaging frame may also include one of aluminum, beryllium copper alloy, titanium alloy, or a combination of any two or more thereof, without limitation.

[0035] Furthermore, the package frame is cleaned to remove pollutants and residues to ensure that the die attach pad of the package frame is clean and free of contamination.

[0036] In step S2, first select a suitable DAF film material, such as an epoxy resin-based DAF film, which has good thermal conductivity, low stress and high adhesion. In some embodiments, in the step of selecting the DAF film, the material of the DAF film may also include one or more combinations of epoxy resin, polyimide, polyimide, polyester, polystyrene, polycarbonate, polyurethane, and acrylic resin, without specific limitation. Then prepare the DAF film, and pre-cut the DAF film into fragments that match the size of the IGBT chip. Then perform the bonding step to ensure that the die attach pad on the frame is clean and pollution-free, and then bond the pre-cut DAF film to the die attach pad of the frame to ensure that the DAF film is accurately aligned with the frame. Then place the IGBT chip, place the IGBT chip on the DAF film, and ensure that the chip and the DAF film are accurately aligned. Finally, perform the baking step, place the bonded IGBT chip in a baking oven, and bake it between 100°C and 150°C. The baking pressure is between 0.1 MPa and 1 MPa, and the baking time is between 3 min and 20 min, which can be set according to the characteristics of the DAF film and the size of the IGBT chip, and are not specifically limited.

[0037] In step S3, the step of applying glue on the surface of the IGBT chip includes: selecting glue, cleaning the surface of the IGBT, applying glue on the surface of the IGBT, and curing. Among them, the glue is XYC-FF06 glue. In some embodiments, the glue can also be one of epoxy resin glue, silicone, hot melt glue, polyurethane glue, and polyimide glue, without specific limitation. Then, the surface of the IGBT chip is cleaned to remove pollutants and residues to ensure that the surface is clean. Then, use precision dispensing equipment to apply an appropriate amount of XYC-FF06 glue on the surface of the IGBT chip to ensure that the glue is evenly covered and does not overflow to the edge of the IGBT chip. Some glues may need to be pre-cured or fully cured at a certain temperature to improve bonding strength and stability.

[0038] In step S4, firstly, a suitable DAF film material is selected, such as an epoxy resin-based DAF film, which has good thermal conductivity, low stress and high adhesion. In some embodiments, in the step of selecting the DAF film, the material of the DAF film may also include one or more combinations of epoxy resin, polyimide, polyimide, polyester, polystyrene, polycarbonate, polyurethane, and acrylic resin, without specific limitation. Then, the DAF film is prepared, and the DAF film is pre-cut into fragments matching the size of the PMOS wafer. Then, a bonding step is performed to ensure that the bonding area on the surface of the IGBT is clean and free of pollution, and then the pre-cut DAF film is bonded to the bonding area on the surface of the IGBT to ensure that the DAF film and the IGBT are accurately aligned. Then, the PMOS wafer is placed, and the PMOS wafer is placed on the DAF film to ensure that the alignment between the PMOS wafer and the DAF film is accurate. Finally, a baking step is performed, and the bonded IGBT chip and the PMOS wafer are placed in a baking furnace and baked at between 100°C and 150°C. The baking pressure is between 0.1 MPa and 1 MPa, and the baking time is between 3 min and 20 min, which can be set according to the characteristics of the DAF film and the size of the IGBT chip, and are not specifically limited.

[0039] In step S5, before bonding, ensure that the bonding pads on the IGBT and PMOS chips are clean and free of contamination. Bond the drain of PMOS to the gate of IGBT: Use aluminum wire (AL wire) to connect the drain pin of PMOS to the gate pin of IGBT. An ultrasonic bonding machine is usually used to weld the aluminum wire to the bonding pads of the chip through heating and ultrasonic vibration. Bond the gate of PMOS to the frame pin: Bond the gate pin of PMOS to a pin on the package frame. Use a similar method to the PMOS drain bonding to ensure that the bond is firm. Bond the emitter of IGBT to the frame pin: Bond the emitter pin of IGBT to another pin on the package frame, also using AL wire bonding. Bond the source of PMOS to the package frame pin: Bond the source pin of PMOS to the third pin on the package frame, which will later be connected to the driver IC on the peripheral PCB. In some embodiments, the metal wire used in the bonding step also includes one of a gold wire, a copper wire, a silver wire, a platinum wire, a nickel wire, a silver alloy wire, and a copper alloy wire, without specific limitation.

[0040] Furthermore, after the bonding step, an inspection and annealing step is also included. The bonding quality is inspected using a microscope or other inspection equipment to ensure that there are no cracks, voids or poor contacts. Low temperature annealing may be required to improve the mechanical and electrical properties of the bond.

[0041] This process flow uses DAF film, glue coating technology and precise bonding to tightly connect IGBT and PMOS to the package frame, achieving better electrical performance control and EMI management.

[0042] according to Figure 3 , Figure 4 As shown, the present invention also provides an IGBT device based on a PMOS tube manufactured by the above manufacturing method, wherein the IGBT gate 22 is connected to the PMOS drain 31 , and the PMOS source 33 is connected to the driver IC 40 .

[0043] according to Figure 5 As shown in the figure, when the di / dt (instantaneous current change) is large during the IGBT switching process, a PMOS tube is set between the IGBT driver IC and the IGBT gate, and its threshold voltage is set to about 4V. When the di / dt generated by the IGBT device switching is large, the IGBT emitter stray inductance will produce a voltage drop, which will increase the conduction voltage drop of the PMOS, thereby increasing the RDSON (on-resistance) of the PMOS itself. The increase in RDSON will increase the gate drive resistance, reduce the IGBT drive current, reduce the IGBT turn-on speed, and thus reduce di / dt to improve EMI.

[0044] Taking the 650V50A IGBT TO247 package as an example, the di / dt when the IGBT is turned on is 695A / us, and the internal integrated inductor of TO247 is about 13nH. When di / dt occurs, a voltage drop of 9V is generated, which means that the gate voltage of PMOS rises from 0V to 9V when it is turned on, which will reduce the channel width of PMOS and increase RDSON, thereby increasing the IGBT drive resistance and reducing the di / dt of the IGBT switching process.

[0045] It can ensure the stable operation of equipment, make the electronic system more stable, extend the product life and improve the product market competitiveness.

[0046] The technical scope of the present invention is not limited to the contents in the above description. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of ​​the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A method for preparing an IGBT device based on a PMOS tube, characterized in that: The following steps are involved: S1. Provide a packaging frame; S2. Compounding the IGBT chip onto the packaging frame by DAF process; S3. Apply glue on the surface of the IGBT chip; S4. Compound the PMOS wafer onto the IGBT chip through the DAF process; S5. Bond the PMOS drain to the IGBT gate, and bond the PMOS gate, IGBT emitter, and PMOS source to the respective pins of the packaging frame; wherein the pin of the packaging frame bonded to the PMOS source is constructed to be suitable for connection with the driver IC of the IGBT device.

2. The method according to claim 1, characterized in that: The packaging frame is made of a material selected from the group consisting of copper, nickel-iron alloy, aluminum, beryllium-copper alloy, and titanium alloy, or a combination of any two or more of the two.

3. The method according to claim 1, characterized in that: In step S2 and step S4, the DAF process steps include: selecting a DAF film, preparing a DAF film, bonding the DAF film, placing an IGBT chip or a PMOS wafer, and baking.

4. The method according to claim 3, characterized in that: In the step of selecting the DAF film, the material of the DAF film includes one or a combination of any two or more of epoxy resin, polyimide, polyimide, polyester, polystyrene, polycarbonate, polyurethane, and acrylic resin.

5. The method according to claim 3, characterized in that: In the step of preparing the DAF film, the DAF film is pre-cut into segments matching the size of the IGBT chip or the size of the PMOS wafer.

6. The method according to claim 3, characterized in that: The baking temperature is between 100° C. and 150° C., the baking pressure is between 0.1 MPa and 1 MPa, and the baking time is between 3 min and 20 min.

7. The method according to claim 1, characterized in that: In the step S3, the step of applying glue on the surface of the IGBT chip includes: selecting glue, cleaning the surface of the IGBT, applying glue on the surface of the IGBT, and curing.

8. The method according to claim 7, characterized in that: The glue is one of XYC-FF06 glue, epoxy resin glue, silicone glue, hot melt glue, polyurethane glue, and polyimide glue.

9. The method according to claim 1, characterized in that: In the step S5, the metal wire used in the bonding step includes one of aluminum wire, gold wire, copper wire, silver wire, platinum wire, nickel wire, silver alloy wire, and copper alloy wire.

10. An IGBT device based on a PMOS tube, characterized in that: The method is described in any one of claims 1 to 9.

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