CN117497497B - A liquid cooling and heat dissipation packaging structure for a power module - Google Patents

Abstract

The present invention belongs to the technical field of semiconductor devices, and specifically relates to a power module liquid-cooled heat dissipation packaging structure. In view of the low heat dissipation efficiency of existing silicon carbide power modules, the present invention adopts the following technical solution: a power module liquid-cooled heat dissipation packaging structure, including a DBC ceramic substrate; a power chip; an inner copper layer, forming an inner cooling channel flowing through the power chip; an outer copper layer, forming an outer cooling channel; a coolant, flowing in the inner cooling channel and the outer cooling channel; a lead, one end of which is connected to the power chip, and the other end is led out through the inner copper layer and the DBC ceramic substrate; the DBC ceramic substrate, the inner copper layer, the power chip, and the outer copper layer are stacked and distributed along the thickness direction and connected as a whole. The beneficial effects of the present invention are: improving the heat dissipation efficiency, reducing the temperature difference between different surfaces, and improving the working reliability of the power chip; compared with the existing double-sided water-cooled heat dissipation structure, the outer copper layer can directly form the outer surface of the packaging structure.

Description

A liquid cooling and heat dissipation packaging structure for a power module

Technical Field

The present invention belongs to the technical field of semiconductor devices, and in particular relates to a liquid-cooled heat dissipation packaging structure for a power module.

Background technique

Silicon carbide power modules have become the focus of research due to their high temperature resistance and high stability in high temperature environments. For example, the power modules for new energy vehicles have gradually entered the development stage with silicon carbide MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET) as the core, from the era dominated by silicon-based IGBT (Insulate-Gate Bipolar Transistor, IGBT).

As the power consumption of silicon carbide power modules increases, heat dissipation becomes an important factor affecting the long-term stable operation of silicon carbide power modules. For high-voltage and high-current high-voltage power modules, only liquid cooling can be used. However, the current liquid cooling methods mostly weld or bond a water cooling plate (interface material) under the DBC (Direct Bond Copper, DBC) ceramic substrate of the power module, and can only cool one side of the chip. For example, in the scheme disclosed in CN116741724A-Cooling integrated silicon carbide module and its preparation method, chip modification method, by setting a manifold layer and setting a microchannel on the chip, the heat dissipation efficiency is improved.

However, the aforementioned patent application still has the following problems: the chip only dissipates heat on one side, there is temperature non-uniformity inside the chip, the surface temperature of the chip where it is bonded to the water cooling plate is the lowest, and the temperature of the chip farthest from the water cooling plate is higher (this surface is usually sealed with epoxy resin). The temperature difference between the two surfaces leads to an internal temperature gradient, which affects the service life of the chip. In addition, as the power increases, in order to ensure the normal operation of the power chip, it is usually necessary to increase the fluid flow rate, which will increase the temperature difference inside the chip and reduce the reliability of the chip. At the same time, the aforementioned patent application only discloses the liquid cooling heat dissipation structure, but does not disclose the complete packaging structure, fails to combine the packaging with liquid cooling, and does not disclose the specific wiring structure. When a double-sided cooling structure is adopted, the packaging and wiring problems still need to be solved.

In addition, although there are power modules with double-sided heat dissipation in the prior art, most of them do not use liquid cooling. In a few double-sided liquid cooling structures, the coolant and the power chip are separated by aluminum shells, copper, epoxy resin, etc., resulting in large thermal resistance, low heat dissipation efficiency, and a relatively complex structure, which still has a lot of room for improvement. At the same time, the existing double-sided liquid cooling packaging structure is mostly encapsulated with epoxy resin, etc.

Summary of the invention

In view of the low heat dissipation efficiency of existing silicon carbide power modules, the present invention provides a power module liquid cooling and heat dissipation packaging structure, which performs multi-faceted liquid cooling on chips, reduces thermal resistance, improves heat dissipation efficiency, and reduces temperature differences.

To achieve the above object, the present invention adopts the following technical solution: a power module liquid cooling and heat dissipation packaging structure, the power module liquid cooling and heat dissipation packaging structure comprising:

DBC ceramic substrate;

Power chip;

The inner copper layer is located between the power chip and the DBC ceramic substrate to form an inner cooling channel flowing through the power chip;

An outer copper layer, forming an outer cooling channel for cooling the outer side of the power chip;

A coolant flows in the inner cooling channel and the outer cooling channel;

Lead wire, one end of which is connected to the power chip, and the other end is led out through the inner copper layer and the DBC ceramic substrate;

Among them, the DBC ceramic substrate, the inner copper layer, the power chip, and the outer copper layer are stacked and distributed along the thickness direction and connected as a whole.

The power module liquid-cooling and heat dissipation packaging structure of the present invention is provided with an inner copper layer and an outer copper layer, the inner copper layer is located between the power chip and the DBC ceramic substrate and forms an inner cooling channel, the outer copper layer forms an outer cooling channel, the coolant flows through the inner cooling channel, the coolant flowing in the inner cooling channel directly flows through the power chip to cool one side of the power chip in the thickness direction, the coolant flowing in the outer cooling channel directly or indirectly flows through the power chip to cool the other side of the power chip in the thickness direction, compared with the single-sided cooling structure of the prior art, the power module liquid-cooling and heat dissipation packaging structure of the present invention dissipates heat from more sides of the power chip, improves the heat dissipation efficiency, and reduces the temperature difference between different sides; the outer copper layer can directly form the outer surface of the packaging structure, without using sealing materials such as epoxy resin as the outer surface of the packaging structure; a new lead lead-out structure is adopted so as not to hinder the realization of double-sided liquid cooling.

As one direction of improving the outer copper layer, the outer cooling channel is isolated from the power chip, thereby avoiding the insulation problem caused by the corrosion of the power chip caused by the coolant in the outer cooling channel, and reducing the insulation requirements of the power chip. The isolation of the outer cooling channel and the power chip is achieved by sealing between the copper layers, which is more reliable than sealing using epoxy resin and other methods.

As another direction of improvement of the outer copper layer, the power chip is insulated after being connected to the lead wire, and the coolant is an insulating coolant. The outer copper layer includes a base, and a water inlet, a heat dissipation groove and a water outlet groove are formed on the base. The water inlet, the heat dissipation groove and the water outlet groove form an external cooling channel, and the power chip is located in the heat dissipation groove. The coolant in the external cooling channel flows through the surface of one side of the power chip in the thickness direction, which improves the heat dissipation effect, but also puts forward higher requirements on the insulation of the power chip.

As an improvement direction for the inner copper layer, the inner copper layer includes a manifold diverter plate and an inner guide plate. The manifold diverter plate is located between the DBC ceramic substrate and the inner guide plate. The manifold diverter plate has a manifold water inlet hole, a diversion manifold and a manifold water outlet hole. The inner guide plate has a through guide groove that penetrates in the thickness direction. The power chip includes a substrate layer, a material layer and a drain. The substrate layer has a microchannel, and the through guide groove connects the microchannel and the diversion manifold.

As an improved direction for the distribution of power chips, the inner copper layer is divided into a first inner copper layer and a second inner copper layer, the outer copper layer is divided into a first outer copper layer and a second outer copper layer, two power chips are arranged between the first inner copper layer and the first outer copper layer, and one power chip is arranged between the second inner copper layer and the second outer copper layer, the projections of the power chips in the inner copper layer and the power chips in the outer copper layer on the horizontal plane (length and width plane) are staggered, and the first outer copper layer and the second outer copper layer form the outer surface in the thickness direction of the packaging structure.

The beneficial effects of the power module liquid-cooling and heat dissipation packaging structure of the present invention are: an inner copper layer and an outer copper layer are provided, the inner copper layer is located between the power chip and the DBC ceramic substrate and forms an inner cooling channel, the outer copper layer is farther away from the DBC ceramic substrate than the chip and forms an outer cooling channel, the coolant flows through the inner cooling channel, the coolant flowing in the inner cooling channel directly flows through the power chip to cool one side of the power chip in the thickness direction, the coolant flowing in the outer cooling channel directly or indirectly flows through the power chip to cool the other side of the power chip in the thickness direction, compared with the single-sided cooling structure of the prior art, the power module liquid-cooling and heat dissipation packaging structure of the present invention dissipates heat from more sides of the power chip, improves the heat dissipation efficiency, reduces the temperature difference between different sides, and improves the working reliability of the power chip; compared with the existing double-sided water-cooling and heat dissipation structure, the outer copper layer can directly form the outer surface of the packaging structure, and there is no need to use sealing materials such as epoxy resin as the outer surface of the packaging structure; a new lead lead-out structure is adopted so as not to hinder the realization of double-sided liquid cooling.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of a liquid-cooled heat dissipation packaging structure for a power module according to a first embodiment of the present invention.

FIG2 is a cross-sectional view of a liquid-cooled heat dissipation packaging structure for a power module according to a first embodiment of the present invention (the dotted arrow indicates the flow direction of the coolant).

FIG. 3 is a structural exploded view of the liquid-cooling and heat dissipation packaging structure of the power module according to the first embodiment of the present invention.

FIG. 4 is a schematic structural diagram of a DBC ceramic substrate of a power module liquid cooling and heat dissipation packaging structure according to the first embodiment of the present invention.

FIG. 5 is a schematic structural diagram of a first manifold shunt plate of a power module liquid cooling and heat dissipation packaging structure according to the first embodiment of the present invention.

FIG. 6 is a schematic structural diagram of a first inner guide plate of a power module liquid-cooling and heat dissipation packaging structure according to the first embodiment of the present invention.

FIG. 7 is a schematic diagram of the structure of a power chip of a power module liquid cooling and heat dissipation packaging structure according to the first embodiment of the present invention.

FIG8 is a schematic structural diagram of a first outer guide plate of a power module liquid cooling and heat dissipation packaging structure according to the first embodiment of the present invention.

FIG. 9 is a schematic structural diagram of a first cover plate of a power module liquid cooling and heat dissipation packaging structure according to the first embodiment of the present invention.

FIG. 10 is a schematic three-dimensional cross-sectional view from another angle of the liquid-cooling and heat dissipation packaging structure of the power module according to the first embodiment of the present invention.

In the figure, 1, DBC ceramic substrate; 11, substrate thickness wiring hole; 12, substrate horizontal wiring hole;

2. power chip; 21. annular sealing portion; 22. groove;

3. First manifold splitter plate; 31. Manifold water inlet hole; 32. Splitting manifold; 33. Manifold water outlet hole; 34. Copper layer thickness wiring hole;

4. a first inner guide plate; 41. a through guide groove;

5. First outer guide plate; 51. Water inlet trough; 52. Outer guide trough; 53. Inner guide trough; 54. Water outlet trough; 55. Middle trough; 56. Accommodating trough;

6. first cover plate; 61. heat sink; 62. heat sink fin;

7. Second manifold splitter plate;

8. Second inner guide plate;

9. Second outer guide plate;

10. Second covering plate;

D. Dispenser;

L. Lead.

Detailed ways

The technical solutions of the embodiments of the present invention are explained and described below, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

1 to 10 , a power module liquid cooling and heat dissipation packaging structure according to a first embodiment of the present invention includes:

DBC ceramic substrate 1;

Power chip 2;

The inner copper layer is located between the power chip 2 and the DBC ceramic substrate 1 to form an inner cooling channel flowing through the power chip 2;

An outer copper layer, forming an outer cooling channel for cooling the outer side of the power chip 2;

A coolant flows in the inner cooling channel and the outer cooling channel;

Lead L, one end of which is connected to the power chip 2, and the other end is led out through the inner copper layer and the DBC ceramic substrate 1;

The DBC ceramic substrate 1, the inner copper layer, the power chip 2, and the outer copper layer are stacked and distributed along the thickness direction and connected as a whole.

Referring to Figures 1 to 3, in this embodiment, the power module liquid cooling and heat dissipation packaging structure includes a DBC ceramic substrate 1, three power chips 2, two inner copper layers (including a manifold diverter plate and an inner guide plate respectively), and two outer copper layers (including an outer guide plate and a cover plate respectively). The power module liquid cooling and heat dissipation packaging structure also includes a liquid distributor D located at both ends, and the liquid distributor D is connected to the inner cooling channel and the outer cooling channel. The liquid distributor D is only briefly illustrated, and the specific structure of the liquid distributor D, such as the channels therein, is not shown. The coolant is not shown in the figure. Starting from the DBC ceramic substrate 1, the first manifold diverter plate 3, the first inner guide plate 4, the two power chips 2, the first outer guide plate 5 and the first cover plate 6 are distributed in sequence in the thickness direction upward, and the second manifold diverter plate 7, the second inner guide plate 8, the two power chips 2, the second outer guide plate 9 and the second cover plate 10 are distributed in sequence in the thickness direction downward. The power module liquid cooling and heat dissipation packaging structure (except the liquid distributor D) is a rectangular parallelepiped as a whole, and the two power chips 2 on the same layer are distributed along the length direction.

The inner copper layer is divided into a first inner copper layer and a second inner copper layer, and the outer copper layer is divided into a first outer copper layer and a second outer copper layer. Two power chips 2 are arranged between the first inner copper layer and the first outer copper layer, and one power chip 2 is arranged between the second inner copper layer and the second outer copper layer. The projections of the two upper power chips 2 and the lower power chip 2 along the thickness direction are staggered. The first outer copper layer and the second outer copper layer form the outer surface of the packaging structure in the thickness direction, that is, the upper surface of the first cover plate 6 and the lower surface of the second cover plate 10 form the upper and lower surfaces of the packaging structure.

Two power chips 2 are arranged above the DBC ceramic substrate 1, and one power chip 2 is arranged below. The power module liquid cooling and heat dissipation packaging structure forms a first inner cooling channel flowing through the two power chips 2 above, and forms a first outer cooling channel flowing through the outer wall of the receiving groove 56 above the two power chips 2 above. The power module liquid cooling and heat dissipation packaging structure forms a second inner cooling channel flowing through a power chip 2 below, and forms a second outer cooling channel flowing through the outer wall of the receiving groove 56 below the power chip 2 below.

Referring to FIG. 4 to FIG. 6 , in this embodiment, a substrate thickness wiring hole 11 and a substrate horizontal wiring hole 12 are provided on the DBC ceramic substrate 1 in the thickness direction, and a copper layer thickness wiring hole 34 is provided on the manifold shunt plate and the inner guide plate of the inner copper layer in the thickness direction, and the substrate horizontal wiring hole 12, the substrate thickness wiring hole 11 and the copper layer thickness wiring hole 34 are connected. There are three groups of six substrate thickness wiring holes 11, three substrate horizontal wiring holes 12, and three substrate horizontal wiring holes 12 have six outlets, which correspond to three power chips 2 respectively, and are used for leading out six leads L. The copper layer thickness wiring hole 34 and the substrate thickness wiring hole 11 are coaxially arranged. The lead L is connected to the drain of the power chip 2 via the substrate horizontal wiring hole 12, the substrate thickness wiring hole 11 and the copper layer thickness wiring hole 34. In order to prevent the lead L from being pressed, a lead groove connected to the copper layer thickness wiring hole 34 is provided between the first inner guide plate 4 and/or the first outer guide plate 5.

Referring to FIG5 , the first manifold diverter plate 3 has a manifold water inlet 31, a diverter manifold 32 and a manifold water outlet 33, and there are two diverter manifolds 32. The first manifold diverter plate 3 is provided with two groups of four copper layer thickness wiring holes 34 that penetrate in the thickness direction. The manifold water inlet 31 and the manifold water outlet 33 are coaxially arranged, and the first manifold diverter plate 3 is also provided with an intermediate groove 55 coaxial with the manifold water inlet 31.

6 , the first inner guide plate 4 has a plurality of through guide grooves 41 penetrating in the thickness direction. The first inner guide plate 4 is provided with two groups of four copper layer thickness wiring holes 34 penetrating in the thickness direction.

Referring to FIG. 7 , in this embodiment, the power chip 2 includes a substrate layer, a material layer and a drain electrode. The substrate layer is insulated, and the substrate layer has convex portions, and grooves 22 are formed between the convex portions. The bottom surface of the convex portion is sealed and connected to the inner copper layer, and a microchannel is formed in the groove 22. The substrate layer insulates the material layer and the drain electrode from the inner copper layer and the outer copper layer, and the drain electrode is connected to the wire. The substrate layer has a microchannel (not shown in the figure), and the through flow guide groove 41 of the first inner flow guide plate 4 connects the microchannel of the power chip 2 and the diversion manifold 32 of the first manifold diversion plate 3. The manifold water inlet 31, the diversion manifold 32, the through flow guide groove 41 and the manifold water outlet 33 form an inner cooling channel.

Referring to FIG8 , the first outer guide plate 5 has a water inlet groove 51 and a water outlet groove 54, and the first outer guide plate 5 has an outer guide groove 52 and an inner guide groove 53 in the thickness direction. A receiving groove 56 having a top wall and an annular side wall is formed on the side of the first outer guide plate 5 facing the power chip 2. The receiving groove 56 is isolated from the external cooling channel, and the power chip 2 is located in the receiving groove 56. Two receiving grooves 56 distributed along the first horizontal direction are formed on the first outer guide plate 5, the power chip 2 has two, the outer guide groove 52 and the inner guide groove 53 each have two, and an intermediate groove 55 is formed between the inner guide groove 53 and the outer guide groove 52.

In this embodiment, the first outer cooling channel is isolated from the power chip 2 by the first outer guide plate 5, so as to ensure that the coolant does not damage the insulation of the power chip 2. The coolant is a conductive coolant such as water.

9 , two heat dissipation grooves 61 are formed on the first cover plate 6 facing the power chip 2, and heat dissipation fins 62 are formed in the two heat dissipation grooves 61. The water inlet groove 51, the outer guide groove 52, the heat dissipation groove 61, the inner guide groove 53 and the water outlet groove 54 form an external cooling channel.

Referring to FIG. 10 , the power chip 2 is a high-power power chip 2. The power chip 2 is connected to the lead L through a copper connecting plate. The receiving groove 56 of the first outer guide plate 5 extends in the width direction and receives the copper connecting plate and the lead L. The substrate layer of the power chip 2 is sealed with the first inner guide plate through an annular sealing portion 21. The coolant in the inner cooling channel is isolated from the conductive part, the copper connecting plate, and the lead of the power chip 2. After the lead L is connected to the copper connecting plate, it is led out through the receiving groove 56 of the power chip 2, the copper layer thickness wiring hole 34 of the first inner guide plate 4, the copper layer thickness wiring hole 34 of the first manifold diverter plate 3, the substrate thickness wiring hole 11 of the DBC ceramic substrate 1, and the substrate horizontal wiring hole 12.

2 , the second manifold shunt plate 7 and the first manifold shunt plate 3 are adapted to different numbers of power chips 2 , and the number and positions of the shunt manifolds 32 and the copper layer thickness wiring holes 34 of the second manifold shunt plate 7 are different from those of the first manifold shunt plate 3 .

In order to adapt to different numbers of power chips 2 , the second inner guide plate 8 and the first inner guide plate 4 have different numbers and positions of through guide grooves 41 and copper layer thickness wiring holes 34 from those of the first inner guide plate 4 .

In order to adapt to different numbers of power chips 2 , the second outer guide plate 9 and the first outer guide plate 5 have different numbers and positions of outer guide grooves 52 , inner guide grooves 53 , and accommodating grooves 56 from those of the first outer guide plate 5 , and there is no middle groove 55 .

In order to adapt to different numbers of power chips 2 , the second cover plate 10 and the first cover plate 6 have different numbers and positions of the heat dissipation slots 61 from those of the first cover plate 6 .

In this embodiment, the DBC ceramic substrate 1, the power chip 2, the first manifold diverter plate 3, the first inner guide plate 4, the first outer guide plate 5 and the first cover plate 6 can be connected by diffusion welding, tin soldering, silver sintering, copper sintering, coating with thermal conductive materials, etc.

To verify the effect of the scheme of the present invention, the common single-side cooling and double-side cooling schemes of the substrate are compared with the scheme of the present invention. The experimental object is a 40 mm×40 mm×2 mm (length×width×height) DBC substrate (1 mm middle ceramic layer, 0.5 mm upper and lower copper), and a 10 mm×10 mm×0.5 mm (length×width×height) power chip is sintered on the upper and lower surfaces of the substrate.

The existing single-sided cooling solution of the substrate adopts a microchannel solution of the substrate ceramic layer: 19 microchannels of 40mm×1mm×1mm (length×width×height) are constructed at equal intervals on the ceramic layer of the DBC substrate.

The existing double-sided cooling solution adopts a double-sided microchannel water-cooling plate solution: based on the single-sided cooling solution of the substrate, a 40mm×40mm×2mm water-cooling plate is bonded to the upper and lower chip surfaces, and 19 microchannels of 40mm×1mm×1mm (length×width×height) are evenly arranged inside the water-cooling plate, for a total of 38 microchannels.

The comparative scheme of the present invention constructs 99 10mm×0.1mm×0.2mm microchannels in the chip substrate, and both chips need to be constructed, with a total of 198 microchannels; in the cover plate area above the chip, 256 cylindrical fins with a diameter of 0.3mm are evenly arranged in the corresponding cover plate area above the chip, and both the upper and lower cover plates need to be arranged and constructed, with a total of 512 fins. The comparative scheme of the present invention is different from the embodiment 1 scheme shown in Figures 1 to 10. In the comparative scheme of the present invention, only one chip is set on the upper and lower sides of the substrate.

In order to control the variables, when the total flow rate is 10g/s, the cooling effects of different schemes on chips with the same calorific value are compared, and the calorific value of the chip is adjusted at the same time. The calorific value of the chip's heat flow varies in the range of 50W, 100W, 150W, 200W, 300W, 400W, 600W, 800W and 1000W.

Taking the highest temperature on the chip surface as the junction temperature and comparison index, the chip junction temperature test results under different schemes are as follows:

The junction temperature of the power device chip should be kept below 150°C to ensure the reliability of the work. As can be seen from the above table, the heat dissipation effect of the comparative solution of the present invention gradually improves with the increase of heat flux density, and the junction temperature can be guaranteed not to exceed 120°C at 1000W/ ^cm2 , effectively improving the heat dissipation effect.

At the same time, since in the solution of the first embodiment, the two chips above the substrate and the one chip below are staggered, there is reason to believe that under equal conditions, the solution of the first embodiment can obtain a lower chip junction temperature than the comparative solution in which the two chips above and below the substrate are not staggered.

The beneficial effects of the power module liquid-cooled heat dissipation packaging structure of the first embodiment of the present invention are as follows: an inner copper layer and an outer copper layer are provided, the inner copper layer is located between the power chip 2 and the DBC ceramic substrate 1 and forms an inner cooling channel, the outer copper layer is farther away from the DBC ceramic substrate 1 than the chip and forms an outer cooling channel, the coolant flows through the inner cooling channel, the coolant flowing in the inner cooling channel directly flows through the power chip 2 to cool one side of the power chip 2 in the thickness direction, the coolant flowing in the outer cooling channel directly or indirectly flows through the power chip 2 to cool the other side of the power chip 2 in the thickness direction, compared with the single-sided cooling structure of the prior art, the power module liquid-cooled heat dissipation packaging structure of the present invention performs heat dissipation on more sides of the power chip 2, improves the heat dissipation efficiency, reduces the temperature difference between different sides, and improves the working reliability of the power chip 2; the outer The cooling channel is isolated from the power chip 2 by sealing between the copper layers, and the inner cooling channel is isolated by sealing the substrate layer of the power chip 2 and the first inner guide plate 4, so as to ensure that the coolant does not contact the conductive parts of the power chip 2, the copper connecting plate, and the lead L, thereby ensuring the insulation performance; the power chip 2, the copper connecting plate, and the lead L are insulated from the inner guide layer and the outer guide layer by insulation treatment (which can be achieved by setting an insulating layer, leaving insulating gaps, etc.), so as to ensure the normal operation of the power chip 2; a unique lead L lead-out structure; compared with the existing packaging structure, the outer copper layer directly forms the outer surface of the packaging structure, and there is no need to use sealing materials such as epoxy resin as the outer surface of the packaging structure; the drain and material layer of the power chip 2 are insulated from the copper layers; and three (or more) power chips 2 can be packaged together, i.e., three-in-one packaging.

In other embodiments, the power chip may be disposed only on one side of the DBC ceramic substrate, and the DBC ceramic substrate forms the outer surface of the packaging structure.

In other embodiments, the power chip is connected to the copper connecting plate and the lead and then insulated, the coolant is an insulating coolant, the outer copper layer includes a base, a water inlet, a heat dissipation groove and a water outlet are formed on the base, the water inlet, the heat dissipation groove and the water outlet form an external cooling channel, the power chip is located in the heat dissipation groove, and the coolant in the external cooling channel directly contacts the power chip (without a copper layer in between). The insulation between the power chip, the copper connecting plate, the lead L and the copper layer is achieved by means of coolant (there is a gap between the conductive part of the power chip, the copper connecting plate, the lead L and the copper layer to accommodate the coolant) or by setting an insulating layer or filling epoxy resin. The outer copper layer can be a copper plate, rather than being assembled by an outer guide plate and a cover plate as in Example 1.

The above is only a specific implementation of the invention, but the protection scope of the invention is not limited thereto. Those skilled in the art should understand that the invention includes but is not limited to the contents described in the above specific implementation. Any modification that does not deviate from the functional and structural principles of the invention will be included in the scope of the claims.

Claims (7)

1. The utility model provides a power module liquid cooling heat dissipation packaging structure which characterized in that: the liquid cooling heat dissipation packaging structure of the power module comprises:

a DBC ceramic substrate (1);

A power chip (2);

An inner copper layer which is positioned between the power chip (2) and the DBC ceramic substrate (1) and forms an inner cooling channel flowing through the power chip (2);

an outer copper layer forming an outer cooling channel for cooling the outside of the power chip (2);

a cooling liquid flowing through the inner cooling channel and the outer cooling channel;

one end of the lead (L) is connected with the power chip (2), and the other end of the lead is led out through the inner copper layer and the DBC ceramic substrate (1);

Wherein, the DBC ceramic substrate (1), the inner copper layer, the power chip (2) and the outer copper layer are distributed in a lamination way along the thickness direction and are connected into a whole;

the external cooling channel is isolated from the power chip (2);

The outer copper layer comprises an outer guide plate and a cover plate, the outer guide plate is located between the cover plate and the inner copper layer, one face of the outer guide plate, facing the power chip (2), forms a containing groove (56) with a top wall and an annular side wall, the containing groove (56) is isolated from the outer cooling channel, and the power chip (2) is located in the containing groove (56).

2. The power module liquid cooling package structure according to claim 1, wherein: the outer deflector is provided with an inlet groove (51) and an outlet groove (54), the outer deflector is provided with an outer guide groove (52) and an inner guide groove (53) in the thickness direction, a heat dissipation groove (61) is formed on one surface of the cover plate facing the power chip (2), and an outer cooling channel is formed by the inlet groove (51), the outer guide groove (52), the heat dissipation groove (61), the inner guide groove (53) and the outlet groove (54).

3. The power module liquid cooling package structure according to claim 2, wherein: two containing grooves (56) distributed along the first horizontal direction are formed on the outer guide plate, two power chips (2) are arranged, two guide outer grooves (52) and two guide inner grooves (53) are arranged, and an intermediate groove (55) is formed between the middle guide inner groove (53) and the guide outer groove (52); a heat dissipation fin (62) is formed in the heat dissipation groove (61).

4. A power module liquid cooling package structure according to any one of claims 1 to 3, wherein: the power chip (2) is a high-power chip (2), the power chip (2) comprises a substrate layer, a material layer and a drain electrode, the substrate layer is provided with an annular sealing part which is in sealing connection with the inner copper layer, the drain electrode is connected with the lead (L) through a copper connecting plate, and the material layer, the drain electrode, the copper connecting plate and the lead (L) are insulated with the outer copper layer.

5. The power module liquid cooling package structure according to claim 4, wherein: the inner copper layer comprises a manifold splitter plate and an inner guide plate, wherein the manifold splitter plate is positioned between the DBC ceramic substrate (1) and the inner guide plate, the manifold splitter plate is provided with a manifold water inlet hole (31), a splitter manifold (32) and a manifold water outlet hole (33), the inner guide plate is provided with a through guide groove (41) communicated in the thickness direction, the substrate layer is further provided with a groove (22), a micro-channel is formed in the groove (22), the through guide groove (41) is communicated with the micro-channel and the splitter manifold (32), and the manifold water inlet hole (31), the splitter manifold (32), the through guide groove (41) and the manifold water outlet hole (33) form an inner cooling channel.

6. A power module liquid cooling package structure according to any one of claims 1 to 3, wherein: the inner copper layer is divided into a first inner copper layer and a second inner copper layer, the outer copper layer is divided into a first outer copper layer and a second outer copper layer, two power chips (2) are arranged between the first inner copper layer and the first outer copper layer, one power chip (2) is arranged between the second inner copper layer and the second outer copper layer, the projections of the power chips (2) in the inner copper layer and the power chips (2) in the outer copper layer along the thickness direction are staggered, and the first outer copper layer and the second outer copper layer form the outer surface of the packaging structure in the thickness direction.

7. The power module liquid cooling package structure according to claim 1, wherein: the power module liquid cooling heat dissipation packaging structure further comprises a liquid separator (D), wherein the liquid separator (D) is communicated with the inner cooling channel and the outer cooling channel;

The DBC ceramic substrate (1), the power chip (2), the inner copper layer and the outer copper layer are integrated through sintering;

A substrate thickness wiring hole (11) and a substrate horizontal wiring hole (12) in the thickness direction are formed in the DBC ceramic substrate (1), a copper layer thickness wiring hole (34) penetrating in the thickness direction is formed in the inner copper layer, the substrate horizontal wiring hole (12), the substrate thickness wiring hole (11) and the copper layer thickness wiring hole (34) are communicated, and a lead (L) is connected with the power chip (2) through the substrate horizontal wiring hole (12), the substrate thickness wiring hole (11) and the copper layer thickness wiring hole (34).