KR102552717B1 - Powermodule - Google Patents

Abstract

The present invention relates to a power module capable of efficiently cooling heat generated from a semiconductor chip and miniaturizing the size of the product, comprising one or more semiconductor chips, a heat dissipation substrate to which the semiconductor chip is bonded, and an upper surface of the heat dissipation substrate. includes a cooler disposed at a position that does not overlap with the semiconductor chip to cool heat generated from the semiconductor chip, wherein the heat dissipation substrate has a first plate on an upper surface on which the semiconductor chip is mounted, and a first plate on an upper surface thereof. It includes a stacked second plate and a third plate on a top surface of which the second plate is stacked, wherein the third plate is a heat pipe for dissipating heat generated from the semiconductor chip.

Description

Power module {POWERMODULE}

The present invention relates to a power module, and more particularly, to a power module capable of efficiently cooling heat generated from a semiconductor chip and miniaturizing the size of the product.

In general, a power module that receives DC power from a battery and supplies power for driving a motor is assembled in an inverter.

Such a power module converts high-voltage direct-current power using a fuel cell and battery into low-voltage direct-current power or low-voltage alternating current power in an eco-friendly vehicle to supply energy to electrical components of the vehicle and power to major driving parts.

On the other hand, in accordance with consumers' demand for high power and increased mileage of eco-friendly vehicles, development of high power density and high efficiency power conversion devices is continuously in progress.

In particular, in the case of a power module, which is one of the key components that determine high power density and high efficiency of a power converter, miniaturization development is the most important to achieve high power density. Depending on the control, whether or not to achieve high power density is determined.

As shown in FIG. 1, the power module includes a semiconductor chip 10, a heat dissipation substrate 20 disposed under the semiconductor chip 10, and a semiconductor chip 10 disposed under the heat dissipation substrate 20. It includes a heat pipe 30 for dissipating heat generated by the switching of and a cooler 40 for cooling the heat generated from the semiconductor chip 10 .

Further, the heat dissipation substrate 20 includes a second plate 22 made of ceramic, and a first plate 21 and a third plate 23 stacked on upper and lower surfaces of the second plate 22, respectively.

Here, the first plate 21 is made of a copper or aluminum substrate, and the third plate 23 is made of the same material as the first plate 21 .

In addition, the semiconductor chip 10 and the heat dissipation substrate 20 are bonded through the mutual adhesive member 11. The adhesive member 11 may use various bonding methods such as a solder method, and the heat dissipation substrate 20 and the heat Pipes 30 are joined to each other through thermal grease 32.

Since these power modules generate heat due to power supply, various cooling structures are applied to cool the heat for stable operation.

Meanwhile, in the conventional power module, guide pins 31 are formed in the heat pipe 30 to increase a cross-sectional area with cooling water so that heat generated in the semiconductor chip 10 can be easily discharged.

For this reason, the size of the conventional power module was inevitably increased.

In addition, heat generated from the semiconductor chip 10 from the semiconductor chip 10 as a heat source to the cooler 40 is transferred to the heat pipe 30, thermal grease 32, the third plate 23, and the second plate 22 ) and at least 6 layers of materials such as the first plate 21 and the adhesive member 11.

Therefore, in the conventional power module, heat generated from the semiconductor chip 10 is accumulated without being discharged to the outside from between the respective layers.

For this reason, the conventional power module has a problem in that the cooling efficiency is not efficient.

In particular, since heat generation increases due to an increase in junction temperature of circuits inside a chip due to high-speed operation and high integration, characteristics of semiconductor chips, such as refresh characteristics, operating speed, and lifespan, may be deteriorated.

The present invention has been proposed in view of the above situation, and an object of the present invention is to provide a power module capable of efficiently cooling heat generated from a semiconductor chip while reducing the size of the power module.

In order to achieve the above object, the power module of the present invention includes one or more semiconductor chips, a heat dissipation substrate to which the semiconductor chip is bonded, and a heat dissipation substrate disposed on the upper surface of the heat dissipation substrate at a position that does not overlap with the semiconductor chip. A cooler for cooling heat generated from a chip, wherein the heat dissipating substrate includes a first plate on which the semiconductor chip is mounted, a second plate on which the first plate is stacked, and the second plate on the upper surface. and a stacked third plate, wherein the third plate is a heat pipe for dissipating heat generated from the semiconductor chip.

The cooler is disposed on the upper surface of the third plate in the lateral direction of the first plate and the second plate.

The cross-sectional length of the third plate is longer than the cross-sectional lengths of the first and second plates.

Inside the third plate, a plurality of first channel walls are formed that extend in a direction opposite to the direction in which the cooler is formed and are spaced apart from each other in a direction perpendicular to the extending direction, and inside the cooler, a plurality of first channel walls are formed. The first channel walls extend in a mutually spaced direction, and a plurality of second channel walls 310 spaced apart from each other are formed in a direction perpendicular to the extending direction.

Thermal grease is applied between the cooler and the third plate.

The first plate is made of either copper or aluminum,

The second plate is made of ceramic, and the third plate is made of the same material as the first plate.

In the vehicle detection sensor according to the present invention, since the third plate is made of the same material as the first plate, it is possible to minimize cracking of the power module due to a difference in thermal expansion coefficient.

In addition, since the third plate is made of a heat pipe that dissipates heat generated from the semiconductor chip, the third plate generally has a thermal conductivity of about 10 to 20 double increase

That is, there is an effect of further increasing the cooling efficiency of the power module.

In addition, the low temperature generated from the third plate is transmitted to the semiconductor chip, and the second plate, the first plate, and the adhesive member, that is, only three components are passed through, so that the heat generation of the semiconductor chip can be more efficiently lowered than the conventional power module. There are possible effects.

In addition, since the third plate has a thickness of about 0.8 mm, the heat dissipation substrate exhibits efficient cooling performance and is miniaturized at the same time, thereby reducing the weight and size of the power module.

In addition, since the cooler is disposed on the upper surface of the third plate in the lateral direction of the first plate and the second plate, there is an effect of reducing the size of the power module by about 70% and miniaturizing it more efficiently.

1 is a cross-sectional view showing a cross section of a power module according to the prior art.
Figure 2 is a perspective view showing a power module according to an embodiment of the present invention.
Figure 3 is a side view showing the side of the power module shown in Figure 2;
4 is a cross-sectional view taken along A-A′ shown in FIG. 2;
5 is a cross-sectional view taken along line BB′ shown in FIG. 2;

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, only these embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is defined by the description of the claims. Meanwhile, terms used in this specification are for describing the embodiments and are not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, "comprises" or "comprising" means the presence or absence of one or more other elements, steps, operations and/or elements other than the recited elements, steps, operations and/or elements; do not rule out additions.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a perspective view showing a power module according to an embodiment of the present invention, FIG. 3 is a side view showing a side of the power module shown in FIG. 2, and FIG. 4 is cut along line AA′ shown in FIG. A cross-sectional view, and FIG. 5 is a cross-sectional view taken along line BB′ shown in FIG. 2 .

Referring to FIGS. 2 to 5 , a power module according to an embodiment of the present invention includes a semiconductor chip 100 , a heat dissipation substrate 200 and a cooler 300 .

The semiconductor chip 100 is composed of one or more than one, and may include switching elements and diodes such as IGBT (INSULATED GATE BIPOLAR TRANSISTOR) and MOSFET (METAL OXIDE SEMICONDUCTOR FIELD-EFFECT TRANSISTOR), and may include a bare chip (BARE CHIP ) can be mounted in the form of

The lower surface of the semiconductor chip 100 is bonded to the upper surface of the heat dissipating substrate 200 via an adhesive member 110 .

The adhesive member 110 may be a thermally conductive thermal interface material (TIM: THERMAL INTERFACE MATERIAL) having adhesive performance and high thermal conductivity, such as nano silver.

In addition, the thermally conductive thermal interface material (TIM) can significantly reduce the contact resistance between the metal surface of the power semiconductor and the heat sink, thereby improving the lifespan and reliability of the power module.

Among the bonding materials (TIM) used as the bonding member 110, a material that is sintered by a constant temperature and pressure or a general solder is used, and the flatness of the heat dissipation substrate 200 can be secured by applying a constant temperature and pressure. .

The heat dissipation substrate 200 is made of direct bonding copper (DBC) or direct bonding aluminum (DBA), and includes a first plate 210, a second plate 220, and a third plate 230.

The first plate 210 serves as an electrical movement path such as the semiconductor chip 100 or an external lead frame (not shown), and the semiconductor chip 100 is mounted on the upper surface.

In addition, the first plate 210 is stacked on the upper surface of the second plate 220, and the second plate 220 is stacked on the upper surface of the third plate 230.

That is, in the heat dissipation substrate 200, the third plate 230, the second plate 220, and the first plate 210 are sequentially stacked.

The first plate 210 is made of either a copper substrate or an aluminum substrate, and the second plate 220 is made of a ceramic substrate.

Also, the third plate 230 is made of the same material as the first plate 210 .

Due to this, it is possible to minimize the cracking of the power module due to the difference in thermal expansion coefficient.

Meanwhile, the third plate 230 is formed of a heat pipe that dissipates heat generated from the semiconductor chip 100 .

The third plate 230 according to an embodiment of the present invention is made of a heat pipe, so that the third plate 23 generally has a degree of transfer of thermal energy compared to the conventional third plate 23 made of only copper or aluminum. The thermal conductivity, which represents , increases about 10 to 20 times.

Therefore, the low temperature generated from the heat pipe is transmitted to the semiconductor chip 100, and the conventional method that has gone through the third plate 23, the second plate 33, the first plate 32 and the adhesive member, that is, the four configurations. Unlike the third plate 23, in one embodiment of the present invention, the third plate 230 is made of a heat pipe, so that the low temperature generated from the third plate 230 is transmitted to the semiconductor chip 100. The two plates 220, the first plate 210, and the adhesive member 110, that is, only three components are passed through, and the heat generation of the semiconductor chip 100 can be reduced more efficiently than the conventional third plate 23. there is.

In addition, since the thermal conductivity of the third plate 230 is high, the high temperature generated from the semiconductor chip 100 is evenly distributed to the third plate 230 , thereby easily reducing heat generation of the semiconductor chip 100 .

For this reason, the third plate 230 is made of a heat pipe, so that the cooling efficiency of the power module can be increased, and the amount of heat generated due to the increase in junction temperature of the circuit inside the chip is reduced according to the high-speed operation and high integration of the power module. Therefore, the characteristics of the semiconductor chip 100, for example, refresh characteristics, operation speed, lifespan, etc., can be further increased compared to the prior art.

Meanwhile, the third plate 230 has a thickness of about 0.8 mm and is the thinnest among existing heat pipes.

Due to this, the heat dissipation substrate 200 exhibits efficient cooling performance and is miniaturized at the same time, thereby reducing the weight and size of the power module.

And, as shown in FIGS. 3 and 4 , the cross-sectional length of the third plate 230 is longer than that of the first plate 210 and the third plate 230 .

Accordingly, the cooler 300 can be easily disposed in the remaining area of the third plate 230 that is not in contact with the first plate 210 and the second plate 220 .

The first channel wall 231 is formed on the third plate 230 .

The first channel wall 231 is formed in plurality inside the third plate 230, extends in the opposite direction from the direction in which the cooler 300 is formed, and is spaced apart from each other in a direction perpendicular to the direction in which the cooler 300 is formed. .

That is, as shown in FIGS. 2 and 4, they extend in the Y-axis direction and are spaced apart from each other at equal intervals in the X-axis direction.

For this reason, a volatile material for the function of the heat pipe may be accommodated between the respective first channel walls 231 .

The cooler 300 cools the heat generated from the semiconductor chip 100 and is disposed on the upper surface of the third plate 230 at a position that does not overlap the first plate 210 and the second plate 220 .

More specifically, the cooler 300 is disposed on the upper surface of the third plate 230 in the lateral direction of the first plate 210 and the second plate 220 .

This is because the cooling efficiency of the third plate 230 of the present invention is increased, unlike the prior art in which the lower surface of the heat dissipation substrate 200 has the same area as the heat dissipation substrate 200 in order to increase the cross-sectional area with the cooling water, the present invention In one embodiment, the cooler 300 can be miniaturized and placed on the upper surface of the third plate 230.

Due to this, the size of the power module can be reduced by about 70% and can be miniaturized more efficiently.

At this time, the cooler 300 is coupled to the third plate 230 via thermal grease 232 .

That is, the thermal grease 232 increases the thermal conductivity between the cooler 300 and the third plate 230, so that the low temperature of the cooler 300 is easily transferred from the semiconductor chip 100 to the third plate 230. It can be transmitted to the high temperature of the third plate 230 can be effectively lowered.

Alternatively, the high temperature of the third plate 230 is efficiently dispersed by the thermal grease 232 to effectively reduce the high temperature of the third plate 230 .

In this cooler 300, a second channel wall 310 is formed.

A plurality of second channel walls 310 are formed inside the cooler 300, and the first channel portions extend in a mutually spaced direction, and a plurality of second channel walls 310 are spaced apart from each other in a direction perpendicular to the extending direction.

That is, as shown in FIGS. 2 and 5, they extend in the X-axis direction and are spaced apart from each other at equal intervals in the Y-axis direction.

Due to this, the cooling water can easily flow between the respective second channel walls 310 .

As described above, in the power module according to the present invention, the third plate 230 is made of the same material as the first plate 210, so that cracking of the power module due to a difference in thermal expansion coefficient can be minimized.

Since the third plate 230 is made of a heat pipe that dissipates the heat generated from the semiconductor chip 100, the third plate 230 generally has less heat energy than the third plate 230 made of only copper or aluminum. The thermal conductivity, which indicates the degree of transfer, increases about 10 to 20 times.

That is, the cooling efficiency of the power module can be further increased.

In addition, the low temperature generated from the third plate 230 is transmitted to the semiconductor chip 100, and only passes through the second plate 220, the first plate 210, and the adhesive member 110, that is, three components, Heat generation of the semiconductor chip 100 can be reduced more efficiently than in the prior art.

Since the thickness of the third plate 230 is about 0.8 mm, the heat dissipation substrate 200 exhibits efficient cooling performance and at the same time is miniaturized, thereby reducing the weight and size of the power module.

Since the cooler 300 is disposed in the lateral direction of the first plate 210 and the second plate 220 from the upper surface of the third plate 230, the size of the power module can be reduced by about 70% and more efficiently miniaturized. there is.

The present invention is not limited to the above-described embodiments, and can be implemented with various modifications within the scope of the technical idea of the present invention.

100: semiconductor chip 110: adhesive member
200: heat sink 210: first plate
220: second plate 230: third plate
231: first channel wall 232: thermal grease
300: cooler 310: second channel wall

Claims (6)

one or more semiconductor chips;
a heat dissipation substrate to which the semiconductor chip is bonded; and
A cooler disposed on the upper surface of the heat dissipation substrate at a position that does not overlap the semiconductor chip to cool the heat generated from the semiconductor chip;
The heat sink,
a first plate on an upper surface of which the semiconductor chip is mounted;
a second plate on which the first plate is stacked on an upper surface; and
Including; a third plate on which the second plate is stacked on an upper surface,
The third plate,
A heat pipe for dissipating heat generated from the semiconductor chip;
the cooler,
Arranged in the lateral direction of the first plate and the second plate on the upper surface of the third plate
in power module.
delete The method of claim 1, wherein the cross-sectional length of the third plate,
Longer than the cross-sectional lengths of the first and second plates
in power module.
The method of claim 1, wherein inside the third plate,
A plurality of first channel walls extending in a direction opposite to the direction in which the cooler is formed and spaced apart from each other in a direction perpendicular to the extending direction are formed;
Inside the cooler,
A plurality of first channel walls extending in a direction spaced apart from each other, and a plurality of second channel walls 310 spaced apart from each other in a direction perpendicular to the extending direction are formed.
in power module.
According to claim 1,
Thermal grease is applied between the cooler and the third plate.
in power module.
According to claim 1,
The first plate is made of either copper or aluminum,
The second plate is made of ceramic,
The third plate is made of the same material as the first plate.
in power module.

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