CN117303930A - Directly coated aluminized ceramic substrate and manufacturing method thereof - Google Patents

Abstract

Embodiments of the present disclosure provide a direct aluminum-coated ceramic substrate and a method of manufacturing the same, the method of manufacturing comprising: providing a ceramic substrate; forming an inorganic layer on the surface of the ceramic substrate; forming an aluminum foil layer on the inorganic layer, and treating the aluminum foil layer and the inorganic layer to form a eutectic phase on the surface of the ceramic substrate. By generating the eutectic phase on the surface of the ceramic substrate, the shear strength and the thermal shock resistance times of the ceramic substrate are improved.

Description

Directly coated aluminized ceramic substrate and manufacturing method thereof

Technical field

Embodiments of the present disclosure belong to the technical field of ceramic substrates, and specifically relate to a directly aluminized ceramic substrate and a manufacturing method thereof.

Background technique

As a key component of the power control and conversion system of hybrid power vehicles, the automotive high-power electronic ceramic aluminum-coated substrate was born with the launch of the Prius (Prius brand car), which was the first Toyota company in the world. Directly coated aluminum ceramic substrate (DBA) is a new type of metal-coated ceramic substrate developed based on DBC (directly coated copper ceramic substrate) process technology. It is generally made of aluminum foil and aluminum nitride ceramics. It can also be like a PCB substrate. A variety of patterns can be etched. Since aluminum has a lower melting point and has relatively better wettability with ceramic substrates than copper, DBA has the following better performance characteristics than DBC:

(1) Excellent thermal shock fatigue resistance;

(2) Good thermal stability;

(3) Light weight, 44% lighter than DBC with the same structure;

(4) Good Al wire bonding ability;

(5) The thermal stress between aluminum and ceramics is relatively small.

However, although DBA in the current related technology has the above-mentioned excellent performance characteristics compared to DBC, it also has some shortcomings: such as poor interface bonding strength, shear strength of only 10MPa; and poor thermal shock resistance. , under the conditions of -40℃~200℃, cracking will occur after 500 thermal shock shocks. Based on this, the inventor designed a directly aluminized ceramic substrate and its manufacturing method, which can effectively improve the bonding force and shear strength of the ceramic substrate surface, and enable the ceramic substrate to withstand more thermal shock shocks without cracking. .

Contents of the invention

Embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art and provide a direct aluminum-coated ceramic substrate and a manufacturing method thereof.

On the one hand, embodiments of the present disclosure provide a method for manufacturing a directly aluminum-coated ceramic substrate, including:

Provide ceramic substrate;

Form an inorganic layer on the surface of the ceramic substrate;

An aluminum foil layer is formed on the inorganic layer, and the aluminum foil layer and the inorganic layer are processed to form a eutectic phase on the surface of the ceramic substrate.

Optionally, forming an inorganic layer on the surface of the ceramic substrate includes:

A Si layer is formed on the surface of the ceramic substrate.

Optionally, forming a Si layer on the surface of the ceramic substrate includes:

Physical vapor deposition technology is used to form a Si layer on the surface of the ceramic substrate.

Optionally, the ceramic substrate is an AlN ceramic substrate, and the thickness of the Si layer ranges from 1 μm to 10 μm.

Optionally, forming an aluminum foil layer on the inorganic layer, and processing the aluminum foil layer and the inorganic layer to form a eutectic phase includes:

An aluminum foil with a preset thickness is placed on the surface of the Si layer, and the aluminum foil and the Si layer are hot-pressed and sintered using a hot-pressing device to form an Al-Si eutectic phase.

Optionally, the aluminum foil and the Si layer are hot-pressed and sintered using hot-pressing equipment to form an Al-Si eutectic phase, including:

A preset mechanical pressure is applied to the aluminum foil and the Si layer, and the aluminum foil and the Si layer are heated to a target temperature. After being kept for a predetermined time, they are placed in a vacuum environment and cooled to obtain the Al-Si eutectic phase.

Optionally, the thickness range of the aluminum foil is 0.3μm~0.1mm; and/or the mechanical pressure range is 1Mpa~10Mpa; and/or the target temperature range is 600°C~700°C; and/or Or, the predetermined time range is 1h~3h.

Optionally, during the hot-pressing sintering process, the mold of the hot-pressing equipment is coated with Mg powder.

Optionally, the thickness of the ceramic substrate ranges from 0.5mm to 1mm.

On the other hand, embodiments of the present disclosure provide a directly coated aluminized ceramic substrate, which is prepared using the manufacturing method described above.

The direct aluminized ceramic substrate and the manufacturing method thereof according to the embodiments of the present disclosure improve the shear strength and thermal shock resistance of the ceramic substrate by generating a eutectic phase on the surface of the ceramic substrate.

Description of drawings

Figure 1 is a schematic flow diagram of a method for manufacturing a directly coated aluminized ceramic substrate according to an embodiment of the present disclosure;

Figure 2 is a schematic diagram of the surface structure of a directly coated aluminized ceramic substrate according to another embodiment of the present disclosure;

Figure 3 is a schematic diagram of the Al-Si eutectic phase on the surface of a directly aluminum-coated ceramic substrate according to another embodiment of the present disclosure; a is the formation diagram of the Al-Si eutectic phase, and b is the enlarged eutectic phase diagram. , c is the eutectic phase element diagram after EDS elemental analysis of b.

Detailed ways

In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, the present disclosure will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, a method for manufacturing a directly aluminum-coated ceramic substrate includes:

S110, provide ceramic substrate.

Specifically, in this step, a ceramic substrate is first provided, and then a series of treatments are performed on the interface layer of the ceramic substrate, that is, the surface of the ceramic substrate, so as to improve the surface bonding force and shear strength of the ceramic substrate. And the number of thermal shock shock resistance is effectively improved. The following description takes the provided ceramic substrate as an AlN (aluminum nitride) ceramic substrate as an example. The thickness range of the AlN ceramic substrate can be exemplarily set to 0.5 mm to 1 mm.

S120. Form an inorganic layer on the surface of the ceramic substrate.

Specifically, referring to FIG. 2 together, in this step, an inorganic layer is formed on the surface of the AlN ceramic substrate. As a specific example, the inorganic layer can be formed using Si (silicon), such as using physical vapor deposition technology to plate a Si layer on the surface of an AlN ceramic substrate. Physical vapor deposition technology includes magnetron, electron beam evaporation, etc. For example, the thickness range of the Si layer plated on the surface of the AlN ceramic substrate can be selected from 1 μm to 10 μm.

S130. Form an aluminum foil layer on the inorganic layer, and process the aluminum foil layer and the inorganic layer to form a eutectic phase on the surface of the ceramic substrate.

Specifically, referring to Figures 2 and 3 together, in this step, an aluminum foil layer is formed on the inorganic layer, and the aluminum foil layer and the inorganic layer that are in contact with each other are processed, so that the aluminum foil layer and the inorganic layer are The eutectic reaction generates a eutectic phase, thereby forming a eutectic phase on the surface of the AlN ceramic substrate to improve the surface bonding force, shear strength and thermal shock resistance of the AlN ceramic substrate.

As an example, as shown in Figures 2 and 3, a Si layer is formed on the surface of the AlN ceramic substrate through step S120, an aluminum foil with a preset thickness is placed on the surface of the formed Si layer, and then the aluminum foil is pressed by a hot pressing device. A hot-pressing sintering process is performed with the Si layer to form an Al-Si eutectic phase on the surface of the AlN ceramic substrate. The Al-Si eutectic phase formed on the surface of the AlN ceramic substrate can effectively improve the surface bonding force, shear strength and thermal shock resistance of the AlN ceramic substrate. It should be noted that during the hot-pressing sintering process of the aluminum foil and the Si layer using hot-pressing equipment, the aluminum foil can be brought into dense contact with the surface of the AlN ceramic substrate and the surface can be made to have no pores, thereby making the AlN ceramic substrate The surface bonding force is effectively improved. The thickness range of aluminum foil can be set from 0.3μm to 0.1mm.

Exemplarily, as shown in Figures 2 and 3, the aluminum foil and the Si layer are hot-pressed and sintered using hot-pressing equipment to form an Al-Si eutectic phase, including: The Si layer is subjected to a preset mechanical pressure F and heated to a target temperature. After being kept for a predetermined time, it is placed in a vacuum environment and cooled to obtain the Al-Si eutectic phase. The formation of the eutectic phase is shown in Figure 3. As shown in a, it can be seen that the Al-Si eutectic phase is formed on the surface of the directly aluminum-coated ceramic substrate. Part a is enlarged to form b. By performing EDS elemental analysis on it, we can see that there is obvious Si element enrichment there. For details, please refer to c.

As a specific example, as shown in Figures 2 and 3, in this step, the AlN ceramic substrate on which the Si layer and the aluminum foil layer are formed is placed in a hot pressing device, and the aluminum foil and silicon layer are uniaxially oriented through the hot pressing device. Pressurized heating, please refer to Figure 2 for the specific form. The hot pressing equipment applies mechanical pressure F from the surface of the aluminum foil to it. The applied mechanical pressure F ranges from 1Mpa to 10Mpa. The hot pressing equipment continues to heat during the pressure application process. The target temperature range of the heating is 600℃~700℃. As An example could be heated to 650°C. After heating to the target temperature, keep it for 1h to 3h, then place it in a vacuum environment for slow cooling. After cooling, an AlN ceramic substrate with an Al-Si eutectic phase formed on the surface can be obtained. And in the AlN ceramic substrate, the aluminum foil is in dense contact with the surface of the AlN ceramic substrate and the surface has no pores. Effectively improves the surface bonding force, shear strength and thermal shock resistance of the AlN ceramic substrate.

For example, during the hot-pressing sintering process, the mold of the hot-pressing equipment is coated with Mg powder. By laying Mg powder, it can be ensured that no oxide will be generated on the surface of the AlN ceramic substrate during the hot pressing sintering process. Further improve the surface bonding force, shear strength and thermal shock resistance of the AlN ceramic substrate.

On the other hand, embodiments of the present disclosure provide a directly coated aluminized ceramic substrate, which is prepared by the manufacturing method described above. For the specific steps of the preparation method, reference can be made to the relevant records mentioned above and will not be described in detail here.

The shear strength of the directly aluminized ceramic substrate prepared by the above preparation method can reach 20MPa after testing, and its thermal shock resistance can be increased to 2,000 times under the conditions of -40°C to 200°C. Effectively improves the surface bonding force, shear strength and thermal shock resistance of the ceramic substrate.

It can be understood that the above embodiments are only exemplary embodiments adopted to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the disclosure, and these modifications and improvements are also regarded as the protection scope of the disclosure.

Claims (10)

1. A method for manufacturing a directly aluminum-coated ceramic substrate, which is characterized in that it includes: Provide ceramic substrate; Form an inorganic layer on the surface of the ceramic substrate; An aluminum foil layer is formed on the inorganic layer, and the aluminum foil layer and the inorganic layer are processed to form a eutectic phase on the surface of the ceramic substrate. 2. The method for manufacturing a directly aluminized ceramic substrate according to claim 1, wherein forming an inorganic layer on the surface of the ceramic substrate includes: A Si layer is formed on the surface of the ceramic substrate. 3. The method for manufacturing a directly aluminum-coated ceramic substrate according to claim 2, wherein forming a Si layer on the surface of the ceramic substrate includes: Physical vapor deposition technology is used to form a Si layer on the surface of the ceramic substrate. 4. The method for manufacturing a directly aluminum-coated ceramic substrate according to claim 3, wherein the ceramic substrate is an AlN ceramic substrate, and the thickness of the Si layer ranges from 1 μm to 10 μm. 5. The manufacturing method of directly coated aluminum ceramic substrate according to claim 2, characterized in that: forming an aluminum foil layer on the inorganic layer, and processing the aluminum foil layer and the inorganic layer to The formation of eutectic phases includes: An aluminum foil with a preset thickness is placed on the surface of the Si layer, and the aluminum foil and the Si layer are hot-pressed and sintered using a hot-pressing device to form an Al-Si eutectic phase. 6. The method for manufacturing a directly aluminum-coated ceramic substrate according to claim 5, characterized in that the aluminum foil and the Si layer are hot-pressed and sintered using hot-pressing equipment to form an Al-Si eutectic. phase, including: A preset mechanical pressure is applied to the aluminum foil and the Si layer, and the aluminum foil and the Si layer are heated to a target temperature. After being kept for a predetermined time, they are placed in a vacuum environment and cooled to obtain the Al-Si eutectic phase. 7. The method for making a directly coated aluminum ceramic substrate according to claim 6, wherein the thickness of the aluminum foil ranges from 0.3 μm to 0.1 mm; and/or the mechanical pressure ranges from 1 Mpa to 10 Mpa; And/or, the target temperature range is 600°C~700°C; and/or, the predetermined time range is 1h~3h. 8. The method for manufacturing a directly aluminum-coated ceramic substrate according to claim 5, characterized in that, during the hot-pressing sintering process, the mold of the hot-pressing equipment is coated with Mg powder. 9. The method for manufacturing a directly aluminized ceramic substrate according to any one of claims 1 to 8, wherein the thickness of the ceramic substrate ranges from 0.5 mm to 1 mm. 10. A directly aluminized ceramic substrate, characterized in that it is prepared by the manufacturing method described in any one of claims 1 to 9.