JPH08191239A - Power semiconductor module - Google Patents

Abstract

PURPOSE: To reduce defective operation and current fluctuation and to stabilize operation by arranging a pair of resistors in a power semiconductor module(PSM) to be connected in parallel with another PSM and arranging a pair of resistors between both PSMs. CONSTITUTION: Gate resistors 14 (Rg1 , Rg2 ) are arranged in the vicinity of gate on respective IGBTs 13 (IGBT1, IGBT2) and a common gates resistor 14 (Rg0 ) is arranged in the vicinity of the outside of a part on which respective gates are connected in parallel. When the IGBTs 13 are switched by switching a gate signal by 2 to 10kHz high frequency, the resonation of gate voltage may be generated between the IGBT1 and the IGBT2 connected in parallel if the resistors Rg1 , Rg2 are not arranged. When the resistors Rg1 , Rg2 are added, turn-on and turn-off operation is slightly moderated but the resonation of the gate voltage can be suppressed. Since gate resistors Rg0 are added in the case of connecting plural modules in parallel, the resonation of the gate voltage can be effectively suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parallel connection circuit of power semiconductor modules, and particularly to a structure of a high voltage IGBT module suitable for large current, high reliability and miniaturization, and an IGBT module in parallel connection. The present invention relates to an IGBT module suitable for operating a turn-on operation and a turn-off operation in a well-balanced manner.

[0002]

2. Description of the Related Art Conventionally, there is a circuit as shown in FIG. 8 as a subordinate firing circuit of a parallel thyristor, and a circuit as shown in FIG. 9 which compensates for the drawbacks of these circuits is proposed in Japanese Patent Publication No. 48068. Has been done. The circuit of FIG. 9 describes that the difference in the turn-on operation can be set to about 2 μs with a simple circuit configuration, and was suitable as a dependent firing circuit of a conventional thyristor.

[0003]

The above-mentioned conventional technique is effective in the case of a self-extinguishing type power semiconductor module (eg, IGBT) capable of high-speed switching operation and ON / OFF operation by a gate voltage signal. Was not shown.

If there is a difference of about 2 μs in the turn-on operation of the parallel self-extinguishing type power semiconductor module as in the prior art, naturally the shared current at turn-on greatly differs. Since this shared current eventually settles to the shared current determined by the ON voltage of the element, the influence of the non-uniform turn-on operation is relatively small when the operating frequency is slow.

However, as the operating frequency becomes faster, the turn-off operation comes in even while the shared current determined by the on-voltage is settled, and the non-uniform effect of the turn-on operation is caused by the turn-off current of both parallel elements. In addition to the difference, it will be the difference in temperature rise.

The turn-off characteristics of the self-extinguishing type power semiconductor module are affected by the turn-off current and temperature, which causes uneven turn-off operation. For this reason, if the turn-on operation is not aligned more than in the past, it is difficult to align the turn-off operation, and the current concentrates on the self-extinguishing type power semiconductor module that turns off with a delay, leading to element deterioration or element destruction. There was a problem of tightening. Further, in the conventional technology, since the gate resistance has a large temperature dependency, the switching loss, the switching withstand amount, and the noise generation differ depending on the operating temperature.
It was difficult to achieve low loss and high breakdown resistance over a wide temperature range.

Further, in the prior art, since a gate resistance is provided for each semiconductor chip (or wafer), it is possible to stabilize the parallel operation of these semiconductor chips (or wafer).
In a power semiconductor module such as T, the operation can be stabilized by providing a gate resistor in each of a plurality of parallel chips in one module. However, IGBTs and the like often use a plurality of modules in parallel, and no effective method has been shown for uniform operation during switching between parallel modules at this time.

An object of the present invention is to provide a power semiconductor module which does not cause deterioration or destruction of the self-extinguishing type power semiconductor module when connected in parallel.

[0009]

A drive circuit for connecting the emitters and collectors of a plurality of power semiconductor chips in parallel inside each other and pulling out their respective main terminals to the outside to turn on / off the internal power semiconductor chips. In the self-extinguishing type power semiconductor module, in which the gate signal line and the emitter signal line are connected to the gate and the emitter of each of the power semiconductor chips, each power semiconductor module contains a plurality of power semiconductor chips. , A first resistor is provided for each power semiconductor chip in the middle of each gate wiring of the power semiconductor chip,
In addition, the second resistor is provided between the portion where the gate portions are connected in parallel and the module external gate terminal.

[0010]

[Function] By providing a gate resistor for each chip and also providing a resistor in the common terminal portion to which these are connected,
While reducing malfunctions such as current oscillation between chips,
Even when modules are connected in parallel, current oscillation between modules can be reduced and operation can be stabilized.

Further, each emitter and each collector of the plurality of self-arc-extinguishing type power semiconductor modules are connected in parallel, and a lead terminal to the outside is connected in the middle of each.
In a parallel connection circuit of self-extinguishing type power semiconductor modules, wherein a gate signal line and an emitter signal line from a drive circuit for turning on and off the power semiconductor module are connected to a gate terminal and an emitter terminal of the respective power semiconductor module, respectively. By arranging at least two types of resistors having different signs of temperature dependence in series between the external terminals of the module and the gate electrodes of the individual power semiconductor chips in the module, the large dependence of the gate resistance is obtained. It realizes low loss and high breakdown strength over a wide operating temperature range.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings by taking an IGBT self-extinguishing type power semiconductor module as an example.

FIG. 1 shows an embodiment of the present invention. In the figure, IGBTs 1 and 2 are connected to a common collector C and an emitter E by an emitter wire 11, respectively. Then, C and E are connected to the outside through the collector terminal 20 and the emitter terminal, respectively. The gate terminal 22 for turning the IGBT on and off is connected to the gates on the IGBTs 1 and 2 via the gate wire 12. In such an IGBT parallel connection circuit, according to the present invention, the gate resistance Rg ₁ ,
It is characterized by arranging Rg ₂ and arranging a common gate resistance Rg ₀ in the vicinity of the outside of the portion where the respective gates are connected in parallel.

In this figure, the IGBT is a high frequency (2 to
When the gate signals are switched at 10 kHz) and switched, IGBTs connected in parallel if there is no Rg ₁ or Rg _2.
1 and the IGBT 2 may cause resonance of the gate voltage. It can be considered that this is because a loop current flows in the circuit due to a difference in chip characteristics and a difference in wiring length of the emitter wire 11.

Here, by adding the gate resistors Rg ₁ and Rg ₂ , turn-on and turn-off are somewhat moderated, but resonance of the gate voltage can be suppressed. Further, as shown in FIG. 2, when a plurality of modules of FIG. 1 are further connected in parallel, adding the gate resistance Rg ₀ is effective in suppressing resonance of the gate voltage in the same manner as above. In FIG. 2, a collector lead terminal 20a, an emitter lead terminal 21a, and a gate lead terminal 22a are shown.

In order not to impair high frequency switching and low loss characteristics, the values of Rg ₁ , Rg ₂ and Rg ₀ are 1 to 10Ω.
The degree is suitable.

FIG. 3 shows an example of a module structure using this embodiment. The power semiconductor chip 13 is brazed on the insulating plate 15 and radiates heat to the base 16. The power semiconductor chip 13 is connected to the emitter terminal 21 via the emitter wire 11 and to the gate terminal 22 via the gate wire 12. Further, the module is covered with a case 17 for hermetically sealing, and the inside thereof is made of insulating resin 1.
Filled with 8. In this figure, Rg ₀ is Rg ₁ , R
It is provided between g ₂ and the gate terminal 22. Furthermore, as shown in FIG. 4, a silicon chip resistors Rg _1, Rg ₂ in FIG. 1, using a thermistor Rg _0, if differently the temperature characteristics of Rg _1, Rg ₂ and Rg _0, Switching loss at high temperature is also reduced, and the life can be extended.

Further, as shown in FIG. 5, Rg ₁ and Rg ₂ are not chip resistors but a TiO ₂ film is formed on the chip surface,
Rg ₁ and Rg ₂ may be substituted, and the number of joints around the power semiconductor chip is reduced, reliability is improved, and cost can be reduced. In this case, Rg ₀ may be a silicon chip resistor.

Further, as shown in FIG. 6, the same effect can be expected if Rg ₀ is not a built-in resistor of the module but is externally attached near the outside of the module gate terminal 22.

Further, as shown in FIG. 7, the same effect can be expected even if the gate wire 12 containing a compound semiconductor is used instead of Rg ₁ and Rg ₂ .

Further, even if Rg ₁ and Rg ₂ are destroyed and short-circuited, if Rg ₀ exists, there is an advantage that the current imbalance is less likely to occur than in the case where there is no imbalance.

The power semiconductor modules of these embodiments also have the advantage that the user can save the trouble of attaching a damping resistor externally, can easily assemble, and can improve the reliability.

[0023]

As described above, according to the present invention, since the gate resonance of the power semiconductor modules connected in parallel can be reduced, it is possible to prevent the element from being deteriorated or destroyed.

Further, by selecting the temperature characteristic of the resistor inside the module, the switching loss can be reduced and the life of the system such as the module and the inverter device is extended.

[Brief description of drawings]

FIG. 1 is a simplified model showing an embodiment of the present invention.

FIG. 2 is a model in which one embodiment of the present invention is further arranged in parallel.

FIG. 3 is a module structure example using an embodiment of the present invention.

FIG. 4 is a graph showing temperature characteristics of a gate resistance that is an embodiment of the present invention.

FIG. 5 is another embodiment of the present invention.

FIG. 6 is another embodiment of the present invention.

FIG. 7 shows another embodiment of the present invention.

FIG. 8 shows another conventional example of the present invention.

FIG. 9 is another conventional example of the present invention.

[Explanation of symbols]

11 ... Emitter wire, 12 ... Gate wire, 13
... power semiconductor chip, 14 ... gate resistance, 15 ... insulating plate, 15a ... copper pattern on insulating plate, 16 ... base plate,
17 ... Case, 18 ... Insulating resin, 20 ... Collector terminal,
20a ... collector lead-out terminal, 21 ... emitter terminal, 2
1a ... Emitter lead terminal, 22 ... Gate terminal, 22a
… Gate extension terminal.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiko Koike 7-1, 1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Shigeki Sekine 7-1, Omika-cho, Hitachi-shi, Ibaraki No. 1 Hitachi Ltd., Hitachi Research Laboratory (72) Inventor Shin Kimura 7-1, 1-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Shinya Koike, Hitachi City, Ibaraki Prefecture 3-1-1, Machi, Hitachi, Ltd. Hitachi factory

Claims (4)

[Claims] 1. An external drive circuit for connecting each emitter and each collector of a plurality of self-arc-extinguishing type power semiconductor chips in parallel and connecting lead terminals to the outside to turn on / off the power semiconductor chips. In a self-extinguishing type power semiconductor module in which the gate signal line and the emitter signal line from the power semiconductor chip are connected to the gate and the emitter of the power semiconductor chip, respectively, each gate wiring of each power semiconductor chip and the module external gate terminal A power semiconductor module, wherein at least one first resistor and at least one second resistor are provided in series between and. 2. The power semiconductor module according to claim 1, wherein a first resistor is provided in the vicinity of each gate wiring of each power semiconductor chip, and a portion for connecting each gate wiring in parallel and a module external gate terminal are provided. A power semiconductor module comprising a second resistor provided therebetween. 3. The power semiconductor module according to claim 1, wherein a first resistor provided in the vicinity of each gate wiring of each power semiconductor chip, a portion connecting each gate wiring in parallel, and a module external gate terminal. Second to be installed in
Power semiconductor module characterized in that the resistance body has a positive temperature characteristic on one side and a negative temperature characteristic on the other side in relation to the resistance value and the temperature. 4. The power semiconductor module according to claim 3, wherein a silicon resistor is used as a first resistor provided in the vicinity of each gate wiring of each power semiconductor chip, and a module in which each gate wiring is connected in parallel is provided. The second resistor provided between the external gate terminal and the thermistor, Ti
A power semiconductor module characterized by using a compound semiconductor such as O ₂ .