A half-bridge IGBT module with multiple chips connected in parallel

Abstract

The present invention discloses a multi-chip parallel half-bridge IGBT module, which aims to solve the technical problem of large difference in turn-on peak current between chips in the existing IGBT module. It includes: a metal substrate and six insulating ceramic linings, on each insulating ceramic lining are arranged four IGBT chips and two FRD chips, the gate of the IGBT chip is set in the middle position of one side of the IGBT chip, and all face the center of the IGBT module, and the gate of the IGBT chip is connected to the gate signal copper foil on the insulating ceramic lining through a bonding wire. The present invention can reduce the turn-on peak current difference between IGBT chips in the module, improve the chip turn-on consistency, and avoid premature failure of a chip.

Description

Technical Field

[0001] The invention relates to a half-bridge IGBT module with multiple chips connected in parallel, belonging to the technical field of power semiconductor devices. Background Art

[0002] IGBT (insulated gate bipolar transistor) can withstand high voltage and provide large current, and is easy to control. It is an important power device for motor control and power inverter. In actual use, in order to achieve high current operation, multiple chips need to be connected in parallel on one bridge arm; especially high-voltage IGBT chips, due to the small rated current of a single chip, often 20-30 chips need to work in parallel; due to the high operating frequency of IGBT, the current imbalance during the opening process will cause the power loss of individual chips to be significantly higher than other chips, and the chip junction temperature is inconsistent, affecting the long-term reliability of the module.

[0003] Existing multi-chip parallel high-voltage and high-current IGBT modules are generally composed of a metal substrate, 6 sets of ceramic liner boards with IGBT chips and FRD chips welded on them, a control signal bus printed circuit board, control signal terminals, three sets of power terminals and copper pillars connecting the ceramic liner boards and the control signal bus printed circuit board. The ceramic liner boards are arranged in two rows, the copper pillar pads are located on one side of the edge of the substrate, and the power terminal pads are located in the middle of the substrate; the arrangement layout of the chips on the insulating ceramic liner boards is exactly the same, and the chip gate is located at one corner of the chip, all facing the center of the module.

[0004] Since the gates of the IGBT chips on the existing IGBT modules are located at a corner of the chip and the gate lines are short, the gate loop inductances of the chips vary greatly, resulting in large differences in the peak currents of the chips when they are turned on. Summary of the invention

[0005] In order to solve the problem of large difference in turn-on peak current between chips in existing IGBT modules, the present invention proposes a half-bridge IGBT module with multiple chips connected in parallel. By improving the layout of chips on the module, the turn-on peak current difference between IGBT chips in the module is reduced, the chip turn-on consistency is improved, and premature failure of a chip is avoided.

[0006] In order to solve the above technical problems, the present invention adopts the following technical means:

[0007] The present invention proposes a multi-chip parallel half-bridge IGBT module, including a metal substrate and six insulating ceramic linings, four IGBT chips and two FRD chips are arranged on each insulating ceramic lining, the gate of the IGBT chip is set in the middle position of one side of the IGBT chip and all face the center of the IGBT module, and the gate of the IGBT chip is connected to the gate signal copper foil on the insulating ceramic lining through a bonding wire.

[0008] Furthermore, the six insulating ceramic liner plates are divided into groups of two and arranged in three rows on the metal substrate; the signal copper column welding point of each insulating ceramic liner plate is close to one edge of the metal substrate, and the power terminal welding point is close to the inner side of the metal substrate.

[0009] Furthermore, the signal copper column welding point includes a gate pad located on the gate copper column welding copper foil and an auxiliary emitter pad located on the auxiliary emitter copper column welding copper foil, the gate pad is welded with a gate copper column, and the auxiliary emitter pad is welded with an auxiliary emitter copper column.

[0010] Furthermore, the power terminal welding point includes a collector pad located on the collector copper foil and an emitter pad located on the emitter copper foil, the collector pad is welded with a collector power terminal, and the emitter pad is welded with an emitter power terminal.

[0011] Furthermore, the four IGBT chips and two FRD chips are divided into two groups, each group has one FRD chip and two IGBT chips, and the two groups of chips are arranged on the left and right sides of the insulating ceramic liner according to the rule that the FDR chip is close to the inner side of the metal substrate and the IGBT chip is close to the outer side of the metal substrate.

[0012] Furthermore, the emitters of two adjacent IGBT chips on either side of the insulating ceramic liner are connected together through an emitter interconnection line.

[0013] Furthermore, a gate driving resistor is welded on the gate signal copper foil, and the gate driving resistor is connected to the gate copper pillar welded copper foil through a bonding wire.

[0014] Furthermore, the collector of the IGBT chip and the cathode of the FRD chip are welded to the collector copper foil on the insulating ceramic liner; the collector of the IGBT chip is connected to the emitter copper foil on the insulating ceramic liner through a bonding aluminum wire cluster, and the anode of the FRD chip is connected to the emitter copper foil on the insulating ceramic liner through a bonding wire cluster; the auxiliary emitter copper column welded copper foil on the insulating ceramic liner is connected to the emitter copper foil through a bonding wire.

[0015] The following advantages can be obtained by using the above technical means:

[0016] The present invention proposes a multi-chip parallel half-bridge IGBT module. When performing chip layout, the gate position of the IGBT chip is changed to reduce the relative difference in the gate line length of each IGBT chip. In addition, the present invention also adds an IGBT chip emitter interconnection line, and the emitters of adjacent IGBT chips are connected through the emitter interconnection line to make the emitter reference voltage of each chip consistent. The gate bonding wire of the IGBT chip is perpendicular to the power circuit current path, and the potential is less disturbed by the power circuit, so that the turn-on consistency of each IGBT chip is improved. The device of the present invention solves the problem of current imbalance during the turn-on process of the multi-chip parallel IGBT half-bridge module, reduces the turn-on peak current difference between the module chips, and reduces the current impact of the turn-on process on the chip, which is conducive to the long-term reliable operation of the module. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a schematic structural diagram of a multi-chip parallel-connected half-bridge IGBT module of the present invention.

[0018] Figure 2 Schematic diagram of arrangement of insulating ceramic liner plates on a metal substrate in an embodiment of the present invention.

[0019] Figure 3 The figure is a schematic diagram of the layout and wiring of the chip on the insulating ceramic liner in an embodiment of the present invention.

[0020] Figure 4 The figure is a schematic diagram of the layout and wiring of the chip on the insulating ceramic liner in the prior art.

[0021] In the figure, 1 is a metal substrate, 2 is an insulating ceramic liner, 3 is a control signal bus printed circuit board, 4 is a control signal terminal, 5 is a power terminal, 6 is a connecting copper pillar, 7 is an IGBT chip, 701 is a collector, 702 is a gate, 703 is an emitter, 8 is an FRD chip, 801 is a cathode, 802 is an anode, 9 is a collector copper foil, 901 is a collector pad, 10 is an emitter copper foil, 1001 is an emitter pad, 11 is an auxiliary emitter copper pillar welding copper foil, 1101 is an auxiliary emitter pad, 12 is a gate copper pillar welding copper foil, 1201 is a gate pad, 13 is a gate signal copper foil, 14 is a bonding aluminum wire cluster, 15 is a bonding wire cluster, 16 is a bonding wire, 17 is an emitter interconnection wire, and 18 is a gate drive resistor. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below in conjunction with the accompanying drawings:

[0023] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They 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. Therefore, they cannot be understood as limitations on the present invention.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 or an electrical connection; it can be a direct connection, or it can be indirectly connected 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.

[0025] The present invention proposes a multi-chip parallel half-bridge IGBT module, such as Figure 1 As shown, it mainly includes a metal substrate 1, an insulating ceramic liner 2, a control signal bus printed circuit board 3, a control signal terminal 4, a power terminal 5 and a connecting copper pillar 6; wherein the control signal terminal includes a gate signal terminal, an auxiliary emitter signal terminal and an auxiliary collector signal terminal; the power terminal includes a collector power terminal and an emitter power terminal; the connecting copper pillar is used for the insulating ceramic liner and the control signal bus printed circuit board, and the connecting copper pillar includes a gate copper pillar and an auxiliary emitter copper pillar.

[0026] like Figure 2 As shown, the metal is basically welded with six insulating ceramic liner plates, which are divided into groups of two and arranged in three rows on the metal substrate. The signal copper column welding point of each insulating ceramic liner plate is close to the edge of the metal substrate, and the power terminal welding point is close to the inner side of the metal substrate.

[0027] The chip layout of each insulating ceramic liner is exactly the same, such as Figure 3 As shown, four IGBT chips 7 and two FRD chips 8 are arranged on each insulating ceramic liner. The IGBT chips and FRD chips are divided into two groups, each group has one FRD chip and two IGBT chips, and the two groups of chips are arranged on the left and right sides of the insulating ceramic liner respectively according to the rule that the FDR chip is close to the inner side of the metal substrate and the IGBT chip is close to the outer side of the metal substrate.

[0028] Collector copper foil 9, emitter copper foil 10, auxiliary emitter copper pillar welding copper foil 11, gate copper pillar welding copper foil 12, and gate signal copper foil 13 are welded in sequence from outside to inside on the insulating ceramic liner. The signal copper pillar welding point in the present invention includes a gate pad 1201 located on the gate copper pillar welding copper foil and an auxiliary emitter pad 1101 located on the auxiliary emitter copper pillar welding copper foil, the gate pad is used to weld the gate copper pillar, and the auxiliary emitter pad is used to weld the auxiliary emitter copper pillar; the power terminal welding point in the present invention includes a collector pad 901 located on the collector copper foil and an emitter pad 1001 located on the emitter copper foil, the collector pad is used to weld the collector power terminal, and the emitter pad is used to weld the emitter power terminal.

[0029] according to Figure 3 It can be seen that in the embodiment of the present invention, the collector 701 of the IGBT chip and the cathode 801 of the FRD chip are welded to the collector copper foil on the insulating ceramic liner, the collector of the IGBT chip is connected to the emitter copper foil on the insulating ceramic liner through a bonding aluminum wire cluster 14, and the anode 802 of the FRD chip is connected to the emitter copper foil on the insulating ceramic liner through a bonding wire cluster 15; the gate 702 of the IGBT chip in the present invention is arranged in the middle position of one side of the IGBT chip and all faces the center of the IGBT module, and the gate of the IGBT chip is connected to the gate signal copper foil on the insulating ceramic liner through a bonding wire 16; the emitters 703 of two adjacent IGBT chips on either side of the insulating ceramic liner are connected together through an emitter interconnection line 17.

[0030] In addition, the gate drive resistor 18 welded on the gate signal copper foil is connected to the gate copper pillar welded copper foil through a bonding wire; the auxiliary emitter copper pillar welded copper foil on the insulating ceramic liner is connected to the emitter copper foil through a bonding wire.

[0031] Figure 4 It is a schematic diagram of the layout and connection of the chip on the insulating ceramic liner in the prior art. It can be seen from the figure that the gate of the IGBT chip in the existing IGBT module is located at a corner of the chip, and there is no emitter interconnection line of the IGBT chip.

[0032] By comparing the IGBT module in the prior art and the IGBT module of the present invention, it can be seen that the present invention moves the gate position of the IGBT chip to the middle position on one side of the chip, which can reduce the relative difference in the gate line length of each IGBT chip, and also increases the IGBT chip emitter interconnection line to make the emitter reference voltage of each chip consistent. The gate bonding wire of the IGBT chip of the present invention is perpendicular to the power circuit current path, and the potential is less disturbed by the power circuit, so that the opening consistency of each IGBT chip is improved, effectively solving the problem of current imbalance during the opening process of the multi-chip parallel IGBT half-bridge module in the prior art, reducing the opening peak current difference between the module chips, and reducing the current impact of the opening process on the chip, which is conducive to the long-term reliable operation of the module.

[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A multi-chip parallel half-bridge IGBT module, comprising a metal substrate and six insulating ceramic liner boards, on each insulating ceramic liner board are arranged four IGBT chips and two FRD chips, characterized in that: The gate of the IGBT chip is arranged in the middle of one side of the IGBT chip and all faces the center of the IGBT module. The gate of the IGBT chip is connected to the gate signal copper foil on the insulating ceramic liner through a bonding wire. The four IGBT chips and two FRD chips are divided into two groups, each group has one FRD chip and two IGBT chips, and the two groups of chips are arranged on the left and right sides of the insulating ceramic liner according to the rule that the FDR chip is close to the inner side of the metal substrate and the IGBT chip is close to the outer side of the metal substrate; The emitters of two adjacent IGBT chips on either side of the insulating ceramic liner are connected together through an emitter interconnection line; The collector of the IGBT chip and the cathode of the FRD chip are welded to the collector copper foil on the insulating ceramic liner; the collector of the IGBT chip is connected to the emitter copper foil on the insulating ceramic liner through a bonding aluminum wire cluster, and the anode of the FRD chip is connected to the emitter copper foil on the insulating ceramic liner through a bonding wire cluster; the auxiliary emitter copper column welded copper foil on the insulating ceramic liner is connected to the emitter copper foil through a bonding wire.

2. A multi-chip parallel half-bridge IGBT module according to claim 1, characterized in that: The six insulating ceramic liner plates are divided into groups of two and arranged in three rows on the metal substrate; the signal copper column welding point of each insulating ceramic liner plate is close to one side of the edge of the metal substrate, and the power terminal welding point is close to the inner side of the metal substrate.

3. A multi-chip parallel half-bridge IGBT module according to claim 2, characterized in that: The signal copper column welding point includes a gate pad located on the gate copper column welding copper foil and an auxiliary emitter pad located on the auxiliary emitter copper column welding copper foil, the gate pad is welded with a gate copper column, and the auxiliary emitter pad is welded with an auxiliary emitter copper column.

4. A multi-chip parallel half-bridge IGBT module according to claim 2, characterized in that: The power terminal welding point includes a collector pad located on the collector copper foil and an emitter pad located on the emitter copper foil, a collector power terminal is welded on the collector pad, and an emitter power terminal is welded on the emitter pad.

5. The multi-chip parallel half-bridge IGBT module according to claim 1, characterized in that: A gate drive resistor is welded on the gate signal copper foil, and the gate drive resistor is connected to the gate copper pillar welded copper foil through a bonding wire.

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