CN116130443A - Double-sided heat dissipation packaging structure of silicon carbide power module for high-temperature environment - Google Patents

Abstract

The application discloses a two-sided heat dissipation packaging structure of carborundum power module for high temperature environment, include: the semiconductor device comprises a bottom DC-ceramic substrate, a DC-metal layer, a bottom AC ceramic substrate, a first AC metal layer, a top DC+ ceramic substrate, a DC+ metal layer, a top AC ceramic substrate, a second AC metal layer, a first SiC power semiconductor device, a second SiC power semiconductor device, a ceramic interlayer, a first anode metal conductive through hole, an AC metal conductive through hole, a second anode metal conductive through hole, a DC-metal wiring terminal, a DC+ metal wiring terminal and an AC metal wiring terminal. According to the method, the aluminum nitride multilayer ceramic substrate is inserted between the two layers of ceramic substrates to serve as an interlayer, mechanical support is provided, the module is guaranteed to have enough mechanical strength, the ceramic interlayer plays the same role of adjusting the height with the metal gasket, but the thermal expansion coefficient is closer to that of a silicon carbide chip, the thermal stress of an interface is reduced, and the reliability of the module is improved.

Description

A silicon carbide power module double-sided heat dissipation packaging structure for high temperature environment

technical field

The present application relates to the field of semiconductor heat dissipation, in particular to a double-sided heat dissipation packaging structure of a silicon carbide power module used in a high temperature environment.

Background technique

Recently, wide-bandgap semiconductor devices with advantages such as high switching frequency, low switching loss, and high operating temperature have shined in the power module industry, and have gradually become key components necessary for aerospace, new energy vehicles, and oil and gas exploration. In order to achieve higher power density, the cooling system of power electronic equipment is required to be as small as possible. The simplest and most direct way is to increase the working temperature of power electronic equipment. Although silicon carbide power chips can theoretically work at a high temperature of 600°C, power modules have always been limited by packaging materials and cannot work in high temperature environments.

The traditional wire-bonded single-sided cooling power module packaging structure can no longer meet the requirements of high-temperature operation due to heat dissipation performance and reliability issues, so the double-sided cooling packaging structure is gradually occupying the market. However, due to the introduction of metal spacers, there will be more connection points in the double-sided heat dissipation structure, and the reliability problem caused by the mismatch of material CTE is still severe; and the top substrate constrains the displacement of each connection point, which will aggravate the Stress issues, deteriorating overall reliability.

In order to alleviate or even solve the above problems, it is particularly critical to develop a silicon carbide power module double-sided heat dissipation package structure with low parasitic parameters, strong heat dissipation capability, and high reliability.

Contents of the invention

Compared with the traditional wire-bonded single-sided heat dissipation package structure, the double-sided heat dissipation package structure has greatly improved the electrothermal performance, but in order to better meet the stringent requirements for reliability in high-temperature application scenarios.

In order to achieve the above object, the application provides the following solutions:

A silicon carbide power module double-sided heat dissipation package structure for high temperature environment, including: bottom DC-ceramic substrate, DC-metal layer, bottom AC ceramic substrate, first AC metal layer, top layer DC+ceramic substrate, DC+metal layer, Top layer AC ceramic substrate, second AC metal layer, first SiC power semiconductor device, second SiC power semiconductor device, ceramic interlayer, first anode metal conductive via, AC metal conductive via, second anode metal conductive via, DC-metal terminal block, DC+ metal terminal block and AC metal terminal block.

Preferably, the top of the underlying DC-ceramic substrate is covered with the DC-metal layer;

The top of the underlying AC ceramic substrate is covered with the first AC metal layer;

The bottom of the top AC ceramic substrate is covered with the second AC metal layer;

The bottom of the top DC+ ceramic substrate is covered with the DC+ metal layer.

Preferably, the first anode metal conductive via, the AC metal conductive via and the second anode metal conductive via are integrated inside the ceramic interlayer.

Preferably, the bottom cathode metal pad of the first SiC power semiconductor device is connected to the DC-metal layer, and the top anode metal pad of the first SiC power semiconductor device is connected to the first anode metal conductive via The lower surface connection;

The bottom cathode metal pad of the second SiC power semiconductor device is connected to the first AC metal layer, and the top anode metal pad of the second SiC power semiconductor device is connected to the bottom of the second anode metal conductive via. surface connection;

The upper surface of the first anode metal conductive via is connected to the second AC metal layer;

The upper surface of the second anode metal conductive via is connected to the DC+ metal layer;

The first AC metal layer and the second AC metal layer are connected through the AC metal conductive via.

Preferably, the DC-metal layer is connected to the DC-metal connection terminal;

The first AC metal layer is connected to the AC metal connection terminal;

The DC+ metal layer is connected to the DC+ metal connection terminal.

Preferably, the DC-metal layer is sintered with the first SiC power semiconductor device and the DC-metal connection terminal through nano-silver;

The first AC metal layer is sintered with the second SiC power semiconductor device and the AC metal connection terminal through nano-silver;

The first anode metal conductive via is sintered with the first SiC power semiconductor device and the second AC metal layer through nano-silver;

The AC metal conductive vias are sintered with the first AC metal layer and the second AC metal layer through nano-silver;

The second anode metal conductive via hole is sintered with the second SiC power semiconductor device and the DC+ metal layer through nano-silver;

The DC+ metal layer and the DC+ metal connection terminal are sintered by nano-silver.

Preferably, the bottom DC-ceramic substrate, the bottom AC ceramic substrate, the top DC+ ceramic substrate and the top AC ceramic substrate are selected from AMB substrates, and the material of the substrates is selected from silicon nitride.

Preferably, the material of the ceramic interlayer is aluminum nitride.

The beneficial effect of this application is:

(1) In the silicon carbide power module double-sided heat dissipation packaging structure of this application, an aluminum nitride multilayer ceramic substrate is inserted between the two ceramic substrates as an interlayer to provide mechanical support and ensure that the module has sufficient mechanical strength;

(2) In the silicon carbide power module double-sided heat dissipation packaging structure of the present application, the ceramic interlayer plays the same role in height adjustment as the metal gasket, but the thermal expansion coefficient is closer to the silicon carbide chip, which reduces interface thermal stress and improves module reliability. ;

(3) The silicon carbide power module double-sided heat dissipation packaging structure of the present application fills the space occupied by the air between the two ceramic substrates with a ceramic interlayer, which not only protects the chip from dust and water vapor to a certain extent, but also protects the chip from dust and water vapor. Improve the dielectric strength between substrates;

(4) In the silicon carbide power module double-sided heat dissipation packaging structure of this application, the ceramic substrate is no longer one piece, but the substrate is divided into blocks according to the functions of the metal layer (such as DC+, AC, DC-), the size of the substrate is smaller, and the simplified The shape of the copper layer of each substrate is improved, the stress problem is alleviated, and the reliability of the module is higher.

Description of drawings

In order to illustrate the technical solution of the present application more clearly, the accompanying drawings used in the embodiments are briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. Technical personnel can also obtain other drawings based on these drawings without paying creative labor.

Fig. 1 is a disassembled view of a double-sided heat dissipation packaging structure of a silicon carbide power module used in a high temperature environment according to an embodiment of the present application;

2 is a schematic diagram of the external structure of the packaging structure of the embodiment of the present application;

FIG. 3 is a cross-sectional view of a package structure of an embodiment of the present application;

FIG. 4 is a schematic diagram of the upper and lower surfaces of the ceramic interlayer in the packaging structure of the embodiment of the present application.

Reference signs:

1. DC-ceramic substrate; 2. DC-metal layer; 3. Bottom AC ceramic substrate; 4. First AC metal layer; 5. Top AC ceramic substrate; 6. Second AC metal layer; 7. Top DC+ ceramic substrate ; 8. DC + metal layer; 9. The first SiC power semiconductor device; 10. The second SiC power semiconductor device; 11. Ceramic interlayer; 12. The first anode metal conductive via; 13. AC metal conductive via; 14. The second anode metal conductive through hole; 15. DC-metal connection terminal; 16. AC metal connection terminal; 17. DC+ metal connection terminal.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

In order to make the above objects, features and advantages of the present application more obvious and comprehensible, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

In this embodiment, as shown in Figures 1-4, a silicon carbide power module double-sided heat dissipation packaging structure for high temperature environments includes: the bottom DC-ceramic substrate 1, the DC-metal layer 2, the bottom AC ceramic substrate 3. The first AC metal layer 4, the top DC + ceramic substrate 7, the DC + metal layer 8, the top AC ceramic substrate 5, the second AC metal layer 6, the first SiC power semiconductor device 9, the second SiC power semiconductor device 10, ceramics Interlayer 11 , first anode metal conductive via 12 , AC metal conductive via 13 , second anode metal conductive via 14 , DC-metal connection terminal 15 , DC+ metal connection terminal 17 and AC metal connection terminal 16 .

The top of the bottom DC-ceramic substrate 1 is covered with a DC-metal layer 2, the top of the bottom AC ceramic substrate 3 is covered with a first AC metal layer 4, the bottom of the top AC ceramic substrate 5 is covered with a second AC metal layer 6, and the top layer of DC+ The bottom of the ceramic substrate 7 is covered with a DC+metal layer 8 . A first anode metal conductive via 12 , an AC metal conductive via 13 and a second anode metal conductive via 14 are integrated inside the ceramic interlayer 11 .

The bottom cathode metal pad of the first SiC power semiconductor device 9 is connected to the DC-metal layer 2, and the top anode metal pad of the first SiC power semiconductor device 9 is connected to the lower surface of the first anode metal conductive via 12;

The bottom cathode metal pad of the second SiC power semiconductor device 10 is connected to the first AC metal layer 4, and the top anode metal pad of the second SiC power semiconductor device 10 is connected to the lower surface of the second anode metal conductive via 14;

The upper surface of the first anode metal conductive via 12 is connected to the second AC metal layer 6, the upper surface of the second anode metal conductive via 14 is connected to the DC+ metal layer 8, the first AC metal layer 4 and the second AC metal layer 6 are connected through AC metal conductive vias 13.

The DC-metal layer 2 is connected to the DC-metal connection terminal 15 , the first AC metal layer 4 is connected to the AC metal connection terminal 16 , and the DC+ metal layer 8 is connected to the DC+ metal connection terminal 17 .

The DC-metal layer 2 is sintered with the first SiC power semiconductor device 9 and the DC-metal connection terminal 15 through nano-silver sintering, the first AC metal layer 4 is sintered with the second SiC power semiconductor device 10 and the AC metal connection terminal 16 through nano-silver sintering, The first anode metal conductive via 12 is sintered with the first SiC power semiconductor device 9 and the second AC metal layer 6 through nano-silver sintering, and the AC metal conductive via 13 is connected with the first AC metal layer 4 and the second AC metal layer 6 through nano-silver sintering. Silver sintering, the second anode metal conductive via 14 is sintered with the second SiC power semiconductor device 10 and the DC+ metal layer 8 through nano-silver sintering, and the DC+ metal layer 8 and the DC+ metal connection terminal 17 are sintered through nano-silver. In this example, the specific sintering process of nano-silver is as follows: apply nano-silver paste to the surface of the part to be sintered, and then attach it to the surface of another part to be sintered, preheat for 10 minutes at 100 ° C, and finally in air or Sintering in a nitrogen atmosphere for 20 minutes, the sintering temperature is 250° C., and the sintering pressure is 10-30 MPa.

The bottom DC-ceramic substrate 1, the bottom AC ceramic substrate 3, the top DC+ceramic substrate 5 and the top AC ceramic substrate 7 use AMB (active metal brazing) substrates, and the material of the substrates is silicon nitride (Si ₃ N ₄ ), wherein, Silicon nitride can not only meet the requirements of mechanical strength and heat dissipation performance, but also better match the thermal expansion coefficient of silicon carbide, reduce thermal stress on the substrate and chip, and improve module reliability. The corresponding area on the silicon nitride ceramic material The AMB process is used for metallization, and the surface of the metal layer is plated with gold, so that the subsequent chip and the metallized area of the ceramic interlayer 11 can be electrically connected through nano-silver sintering; the material of the ceramic interlayer 11 is aluminum nitride (AlN), wherein aluminum nitride Ceramic has good thermal performance and a coefficient of thermal expansion close to that of silicon carbide, which improves reliability. In this embodiment, the first anode metal conductive via hole 12 , the AC metal conductive via hole 13 , and the second anode metal conductive via hole 14 inside the ceramic interlayer 11 use tungsten as the filling metal.

The above-mentioned embodiments are only a description of the preferred mode of the application, and are not intended to limit the scope of the application. Variations and improvements should fall within the scope of protection determined by the claims of the present application.

Claims (8)

1. A silicon carbide power module double-sided heat dissipation package structure for high temperature environment, characterized in that it includes: bottom DC-ceramic substrate, DC-metal layer, bottom AC ceramic substrate, first AC metal layer, top layer DC+ceramic Substrate, DC+ metal layer, top AC ceramic substrate, second AC metal layer, first SiC power semiconductor device, second SiC power semiconductor device, ceramic interlayer, first anode metal conductive via, AC metal conductive via, second Anodized metal conductive vias, DC-metal terminals, DC+ metal terminals and AC metal terminals. 2. A double-sided heat dissipation packaging structure for a silicon carbide power module used in a high temperature environment according to claim 1, characterized in that, the DC-metal layer is coated on top of the underlying DC-ceramic substrate; The top of the underlying AC ceramic substrate is covered with the first AC metal layer; The bottom of the top AC ceramic substrate is covered with the second AC metal layer; The bottom of the top DC+ ceramic substrate is covered with the DC+ metal layer. 3. A silicon carbide power module double-sided heat dissipation packaging structure for high temperature environment according to claim 1, characterized in that, the first anode metal conductive via hole, the AC metal interlayer are integrated inside the ceramic interlayer. conductive vias and the second anode metal conductive vias. 4. A silicon carbide power module double-sided heat dissipation package structure for high temperature environment according to claim 1, characterized in that, The bottom cathode metal pad of the first SiC power semiconductor device is connected to the DC-metal layer, and the top anode metal pad of the first SiC power semiconductor device is connected to the lower surface of the first anode metal conductive via. connect; The bottom cathode metal pad of the second SiC power semiconductor device is connected to the first AC metal layer, and the top anode metal pad of the second SiC power semiconductor device is connected to the bottom of the second anode metal conductive via. surface connection; The upper surface of the first anode metal conductive via is connected to the second AC metal layer; The upper surface of the second anode metal conductive via is connected to the DC+ metal layer; The first AC metal layer and the second AC metal layer are connected through the AC metal conductive via. 5. A silicon carbide power module double-sided heat dissipation package structure for high temperature environment according to claim 1, characterized in that, The DC-metal layer is connected to the DC-metal connection terminal; The first AC metal layer is connected to the AC metal connection terminal; The DC+ metal layer is connected to the DC+ metal connection terminal. 6. A double-sided heat dissipation packaging structure for a silicon carbide power module used in a high temperature environment according to claim 1, characterized in that, The DC-metal layer is sintered with the first SiC power semiconductor device and the DC-metal connection terminal through nano-silver; The first AC metal layer is sintered with the second SiC power semiconductor device and the AC metal connection terminal through nano-silver; The first anode metal conductive via is sintered with the first SiC power semiconductor device and the second AC metal layer through nano-silver; The AC metal conductive vias are sintered with the first AC metal layer and the second AC metal layer through nano-silver; The second anode metal conductive via hole is sintered with the second SiC power semiconductor device and the DC+ metal layer through nano-silver; The DC+ metal layer and the DC+ metal connection terminal are sintered by nano-silver. 7. A silicon carbide power module double-sided heat dissipation packaging structure for high temperature environment according to claim 1, characterized in that, the bottom DC-ceramic substrate, the bottom AC ceramic substrate, and the top DC+ceramic substrate And the top-layer AC ceramic substrate is selected from AMB substrate, and the material of the substrate is selected from silicon nitride. 8 . The silicon carbide power module double-sided heat dissipation package structure for high temperature environment according to claim 1 , wherein the ceramic interlayer is made of aluminum nitride.

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