Metal ceramic composite substrate and processing technology thereof

Abstract

The invention relates to the technical field of metal ceramic processing, in particular to a metal ceramic composite substrate and a processing technology thereof.The metal ceramic composite substrate comprises a metal ceramic composite substrate body, the metal ceramic composite substrate body comprises an upper metal ceramic plate, a lower metal ceramic plate and a transition layer, the upper metal ceramic plate is inserted into the top of the transition layer, and the lower metal ceramic plate is inserted into the bottom of the transition layer; and the lower metal ceramic plate is inserted into the bottom of the transition layer. The CTE of the lower metal ceramic plate serving as the transition layer is between that of metal and that of ceramic, and the lower metal ceramic plate with the intermediate value of the thermal expansion coefficients is placed between the metal and the ceramic due to different thermal expansion coefficients of the metal, the metal ceramic plate and the transition layer, so that the upper metal ceramic plate or the transition layer can be prevented from falling off due to excessive heat difference when being heated; and the thermal stress is relieved through gradient transition.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cermet processing, and particularly relates to a cermet composite substrate and a processing technology thereof. BACKGROUND

[0002] The cermet composite substrate is a high-performance material combined by metal (such as copper, aluminum and stainless steel) and ceramic (such as aluminum oxide, aluminum nitride and silicon carbide) through a composite process, and has high thermal conductivity and electrical conductivity of metal and high insulation and high temperature resistance of ceramic, and is a key basic material in the fields of electronic packaging, power devices and aerospace.

[0003] 1. The interface of metal and ceramic is weak due to atomic bonding, that is, the metal bond and the ionic bond are incompatible, and the interface defects (microcracks and pores) are many, resulting in low shear strength, and the interface of metal and ceramic is easy to debond under long-term thermal cycle or mechanical vibration, causing thermal resistance to increase or device short circuit. 2. Due to the large difference in CTE between metal and ceramic, under temperature fluctuation, that is, due to the inconsistent expansion or shrinkage rate in-55 DEG C-150 DEG C, periodic tensile or compressive stress is generated at the interface of metal and ceramic, which eventually leads to microcrack propagation and finally failure. SUMMARY

[0004] The present application aims at the problems in the background art and provides a cermet composite substrate and a processing technology thereof.

[0005] The technical scheme of the present application is as follows: A cermet composite substrate comprises: The cermet composite substrate comprises an upper cermet plate, a lower cermet plate and a transition layer, the upper cermet plate is inserted on the top of the transition layer, and the lower cermet plate is inserted on the bottom of the transition layer. The thermal expansion coefficient of the upper cermet plate is greater than that of the transition layer, and the thermal expansion coefficient of the transition layer is greater than that of the lower cermet plate. Optionally, the outer side of the cermet composite substrate is adhered with an external adhesive coating.

[0006] Optionally, the upper and lower sides of the transition layer are fixedly installed with transition layer positioning faces, and the outer side of the transition layer positioning face is fixedly installed with multiple groups of transition plates.

[0007] Optionally, the front and rear ends of the transition plate are fixedly installed with two groups of arc-shaped positioning plates.

[0008] Optionally, the side of the transition plate away from the transition layer positioning face is fixedly installed with multiple groups of clamping strips, and the multiple groups of clamping strips are installed between the two groups of arc-shaped positioning plates.

[0009] Optionally, transition plates are arranged between the arc-shaped positioning plate and the clamping strip and between every two groups of clamping strips.

[0010] Optionally, a side of the lower cermet plate towards the transition layer positioning surface is fixedly installed with an installation groove.

[0011] Optionally, a plurality of limiting interlayer blocks are fixedly installed inside the installation groove, and a hollow placement cavity is arranged between every two groups of limiting interlayer blocks.

[0012] Optionally, the arc-shaped positioning plate and the clamping strip are inserted into the hollow placement cavity, and the limiting interlayer block is inserted into the transition plate.

[0013] In another aspect, the application provides a processing technology of a cermet composite substrate, which is used for processing the above cermet composite substrate and includes the following steps. S1, the metal and ceramic blanks are pretreated, and a plurality of transition plates arranged in a whole strip are provided with arc-shaped positioning plates and clamping strips by a machine tool processing mode, and then the arc-shaped positioning plates and the clamping strips are inserted into the hollow placement cavity. S2, a transition layer is arranged between every two ceramic blanks and the metal, and the transition layers are inserted and installed in a stack, and then the activated ceramic blanks, the metal and the transition layers are placed into a graphite mold coated with boron nitride lubricant. S3, the ceramic blanks are heated to form densification, and after pressure forming, the cermet composite substrate is placed for heat preservation, and after the cermet plate is cooled to room temperature, the composite substrate is obtained by demolding.

[0014] In summary, the application includes at least one of the following beneficial technical effects: 1, the transition layer is arranged between the metal and the ceramic, and because the thermal expansion coefficients of the three are different, the transition layer with an intermediate thermal expansion coefficient is arranged between the metal and the ceramic, so that when the upper cermet plate or the lower cermet plate is heated, the difference in heat can be avoided to prevent the cermet plate from falling off, and the thermal stress is relieved by gradient transition; 2, the relative resistance is formed by the insertion and installation of the multi-layer material, thereby improving the stability of the cermet composite substrate, and the stability of the atomic bond between the metal and the ceramic interface is improved by using different material mixing to replace part of the contact surface of the metal and the ceramic. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 FIG. 1 is a structural schematic diagram of a cermet composite substrate; Figure 2 FIG. 2 is a structural schematic diagram of a lower cermet plate of the application; Figure 3Structure diagram of the transition layer of the present application; Figure 4 Structure diagram of the upper metal ceramic plate of the present application Figure 3 Enlarged view of the A part in the middle; Figure 5 Structure diagram of the positioning surface of the metal ceramic plate of the present application Figure 6 Structure diagram of the upper metal ceramic plate of the present application Figure 5 Enlarged view of the B part in the middle; Figure 7 Structure diagram of the external adhesive coating of the present application.

[0016] Reference signs: 1, metal ceramic composite substrate; 101, upper metal ceramic plate; 102, lower metal ceramic plate; 1021, metal ceramic plate positioning surface; 1022, hollow placement cavity; 1023, limiting clamping layer block; 103, transition layer; 1031, transition layer positioning surface; 1032, arc-shaped positioning plate; 1033, transition plate; 1034, clamping strip; 2, external adhesive coating. DETAILED DESCRIPTION

[0017] The technical solutions of the present application will be further described in detail below in combination with the drawings and specific embodiments.

[0018] The components of the embodiments of the present application generally described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application.

[0019] Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0020] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present application, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood broadly, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through intermediate medium, can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0022] As Figures 1 to 7 As shown in the figure, the present application provides a kind of cermet composite substrate, comprising: cermet composite substrate 1, cermet composite substrate 1 includes upper cermet plate 101, lower cermet plate 102 and transition layer 103, upper cermet plate 101 is inserted at the top of transition layer 103, lower cermet plate 102 is inserted at the bottom of transition layer 103, the thermal expansion coefficient of upper cermet plate 101 is greater than the thermal expansion coefficient of transition layer 103, the thermal expansion coefficient of transition layer 103 is greater than the thermal expansion coefficient of lower cermet plate 102, transition layer 103 is made of nickel-phosphorus alloy, the material of upper cermet plate 101 and lower cermet plate 102 can be ceramic or metal, and the composition of upper cermet plate 101 and lower cermet plate 102 is opposite state, if the main component of upper cermet plate 101 is ceramic, then the main component of lower cermet plate 102 is metal, and then upper cermet plate 101, transition layer 103 and lower cermet plate 102 are sequentially carried in the mode of "metal-transition layer-ceramic" multilayer structure, since the thermal expansion coefficient of transition layer 103 is between metal and ceramic, and the thermal expansion coefficients of the three are different, the transition layer 103 with intermediate thermal expansion coefficient is placed between them, so that upper cermet plate 101 or lower cermet plate 102 can avoid large heat difference when heated, and fall off, and then the thermal stress is relieved by gradient transition.

[0023] As an implementation form, the upper and lower sides of the transition layer 103 are fixedly installed with transition layer positioning faces 1031, the outer sides of the transition layer positioning faces 1031 are fixedly installed with multiple groups of transition plates 1033, the front and rear ends of the transition plates 1033 are fixedly installed with two groups of arc-shaped positioning plates 1032, the side of the transition plate 1033 away from the transition layer positioning face 1031 is fixedly installed with multiple groups of clamping strips 1034, the multiple groups of clamping strips 1034 are installed between the two groups of arc-shaped positioning plates 1032, the transition plates 1033 are arranged between the arc-shaped positioning plates 1032 and the clamping strips 1034 and between every two groups of clamping strips 1034, and the arc-shaped positioning plates 1032, the transition plates 1033 and the clamping strips 1034 are sequentially inserted into the hollow accommodation cavities 1022 when the upper metal ceramic plate 101, the lower metal ceramic plate 102 and the transition layer 103 are sequentially inserted and installed, and then when the upper metal ceramic plate 101 or the lower metal ceramic plate 102 is inserted into the transition layer 103, the upper metal ceramic plate 101, the lower metal ceramic plate 102 and the transition layer 103 can be assembled according to the specified area because the shapes and specifications of the upper metal ceramic plate 101, the lower metal ceramic plate 102 and the transition layer 103 are fixedly set, and the outer side of the metal ceramic composite substrate 1 is adhered with an external adhesive coating 2, so that the upper metal ceramic plate 101, the lower metal ceramic plate 102 and the transition layer 103 are fixed by smearing the external adhesive coating 2 later.

[0024] As an implementation form, as shown in Figures 3 to 7 the lower metal ceramic plate 102 in the embodiment is fixedly installed with 1021 on the side facing the transition layer positioning face 1031, the side of 1021 facing the transition layer positioning face 1031 is provided with an installation groove, multiple groups of limiting clamping layer blocks 1023 are fixedly installed in the installation groove, hollow accommodation cavities 1022 are arranged between every two groups of limiting clamping layer blocks 1023, the arc-shaped positioning plates 1032 and the clamping strips 1034 are inserted into the hollow accommodation cavities 1022, and the limiting clamping layer blocks 1023 are inserted into the transition plates 1033.

[0025] In detail, the internal mechanism of the upper and lower metal ceramic plates 101 and 102 is consistent, and both are provided with hollow accommodation cavities 1022 and limiting interlayer blocks 1023, except that the metal content and ceramic content between the two are different. As shown in the figure, due to the different thermal expansion coefficients of the upper metal ceramic plate 101, the transition layer 103 and the lower metal ceramic plate 102, the degree of thermal expansion at high temperature is also different. Since the metal ceramic composite substrate 1 is manufactured by heating forming as the last step of the processing technology, the thermal expansion coefficients of the respective materials of the limiting interlayer blocks 1023, the clamping strips 1034 and the arc-shaped positioning plates 1032 are different. At this time, the thermal expansion distance between each other produces an error, and the deformation of the clamping strips 1034 and the arc-shaped positioning plates 1032 is smaller than that of the limiting interlayer blocks 1023. Therefore, the limiting interlayer blocks 1023 on the lower metal ceramic plate 102 expand in turn to press the side walls of the clamping strips 1034 and the arc-shaped positioning plates 1032. If the deformation coefficient of the clamping strips 1034 and the arc-shaped positioning plates 1032 is greater than that of the limiting interlayer blocks 1023, the clamping strips 1034 and the arc-shaped positioning plates 1032 expand in turn to press the side walls of the limiting interlayer blocks 1023. It is to be noted that the number of limiting interlayer blocks 1023, clamping strips 1034 and arc-shaped positioning plates 1032 shown in the figure is not all, and more groups can be set to improve the anti-deformation ability of the metal ceramic composite substrate 1, so that the metal ceramic composite substrate 1 is more stable in use. When the metal ceramic composite substrate 1 is in a relatively hot or cold environment, the insertion type installation of the multi-layer material can form a relative resistance, thereby improving the stability of the metal ceramic composite substrate. At the same time, by mixing different materials to replace part of the metal and ceramic contact surface, the stability between the atomic bonds of the metal and ceramic interface is improved.

[0026] On the other hand, the application provides a processing technology of a metal ceramic composite substrate, comprising the following steps: S1, chemical degreasing: chemical degreasing is used to remove oil stains on the metal surface, and the composition of chemical degreasing is acetone plus sodium hydroxide solution, and then the metal surface is rinsed with deionized water and dried at a temperature of 100°C for 2 hours; S2, surface activation: etching the copper surface by micro-etching liquid. It is to be noted that the micro-etching liquid composition contains sodium persulfate and sulfuric acid, and the etching rate is 5-10 μm / min, thereby forming a micro-rough structure on the surface of the metal copper, thereby increasing the contact area of the metal copper and the ceramic; S3, ultrasonic cleaning: then the metal copper is thrown into the ultrasonic cleaning equipment, the ultrasonic cleaning equipment removes the particles with particle size >1 μm on the surface of the metal copper after micro-etching by releasing ultrasonic waves, so as to avoid the pollution of the residual particles on the whole processing interface after micro-etching; S4, powder preparation: the ceramic is synthesized into ceramic powder by a solid phase reaction method, it is explained that the ceramic powder is high purity, the purity is >99.9%, and the average particle size of the powder is 0.5 μm-1 μm, and 5%-10% polyvinyl alcohol binder is added in the ceramic powder, and the ceramic powder is prepared into spherical particles by a spray granulation method, and the particle size of the spherical particles is 50 μm-100 μm, then the ceramic powder in the form of spherical particles is dry-pressed, the pressure range of dry-pressing is 500 MPa-100 MPa, then the ceramic powder in the form of spherical particles is made into a ceramic green body, the thickness range of the ceramic green body is 0.5 mm-2 mm, then the green body is heated to 600 ℃ at a rate of 2 ℃ / min in a muffle furnace, and the embryo after heating is kept for 2 h, and then the polyvinyl alcohol binder in the embryo is removed; S5, the metal and the ceramic green body are placed in a radio frequency plasma device, and the metal and the ceramic green body are treated for 5-10 minutes, the surface of the metal and the ceramic green body is bombarded by high-energy plasma, the oxide layer on the surface of the metal and the ceramic green body is removed, and the surface energy of the two is increased, the surface energy of the metal is increased from 30 mN / m to 50 mN / m, and the surface energy of the ceramic is increased from 20 mN / m to 40 mN / m; S6, installation preparation: a fiber laser is used to etch the surface of the metal, a plurality of hollow accommodation cavities 1022 are formed on the surface of 1021, so that a plurality of limiting clamping layer blocks 1023 are formed on 1021, then the front and back sides of the transition layer 103 are processed by a machine tool, a plurality of groups of transition plates 1033 arranged in a whole are provided with arc-shaped positioning plates 1032 and clamping strips 1034, and the arc-shaped positioning plates 1032 and the clamping strips 1034 are inserted into the hollow accommodation cavities 1022, so as to increase the mechanical locking effect between the ceramic embryo and the metal; S7, material placement: the activated copper sheet and the ceramic green body are alternately stacked, that is, the upper metal ceramic plate 101 and the lower metal ceramic plate 102 are alternately stacked, and a layer of transition layer 103 is arranged between every two activated copper sheets and ceramic green bodies, and the two are inserted and installed for stacking, then the activated copper sheet and the ceramic green body are placed into a graphite mold coated with boron nitride lubricant; S8, heating forming: then hot-press sintering metal and ceramic body, and the temperature inside the heating equipment is raised to 1200℃ at a rate of 10℃ / min, since the melting point of copper is 1083℃, and the ceramic body starts to be densified, and a pressure of 150MPa is applied, at this time the metal and ceramic body are diffusion bonded, and the formed metal ceramic composite substrate 1 is kept for 2h; S9, cooling and demolding: after the metal ceramic plate is cooled to room temperature, the composite substrate is demolded, and the surface of the metal ceramic composite substrate 1 is treated by mechanical polishing and chemical cleaning, so that the quality of the metal ceramic composite substrate 1 is improved.

[0027] The above specific embodiments are only several optional embodiments of the present application, and based on the technical solutions of the present application and the related inspiration of the above embodiments, those skilled in the art can make various alternative improvements and combinations on the above specific embodiments.

Claims

1. A metal-ceramic composite substrate, characterized in that, include: Metal-ceramic composite substrate (1), the metal-ceramic composite substrate (1) includes an upper metal-ceramic plate (101), a lower metal-ceramic plate (102) and a transition layer (103), the upper metal-ceramic plate (101) is inserted into the top of the transition layer (103) and the lower metal-ceramic plate (102) is inserted into the bottom of the transition layer (103); The coefficient of thermal expansion of the upper metal-ceramic plate (101) is greater than that of the transition layer (103), and the coefficient of thermal expansion of the transition layer (103) is greater than that of the lower metal-ceramic plate (102).

2. The metal-ceramic composite substrate according to claim 1, characterized in that, The outer side of the metal-ceramic composite substrate (1) is bonded with an external adhesive coating (2).

3. The metal-ceramic composite substrate according to claim 2, characterized in that, The transition layer (103) has a transition layer positioning surface (1031) fixedly installed on both the upper and lower sides, and multiple sets of transition plates (1033) are fixedly installed on the outer side of the transition layer positioning surface (1031).

4. The metal-ceramic composite substrate according to claim 3, characterized in that, The transition plate (1033) is fixedly equipped with two sets of arc-shaped positioning plates (1032) at both the front and rear ends.

5. A metal-ceramic composite substrate according to claim 4, characterized in that, Multiple sets of locking strips (1034) are fixedly installed on the side of the transition plate (1033) away from the transition layer positioning surface (1031), and the multiple sets of locking strips (1034) are installed between two sets of arc-shaped positioning plates (1032).

6. The metal-ceramic composite substrate according to claim 5, characterized in that, A transition plate (1033) is provided between the arc-shaped positioning plate (1032) and the locking strip (1034), as well as between every two sets of locking strips (1034).

7. A metal-ceramic composite substrate according to claim 6, characterized in that, The lower metal ceramic plate (102) is fixedly installed with (1021) on the side facing the metal ceramic plate positioning surface transition layer (103), and the side facing the transition layer positioning surface (1031) of (1021) is provided with an installation groove.

8. A metal-ceramic composite substrate according to claim 7, characterized in that, Multiple sets of limiting interlayer blocks (1023) are fixedly installed inside the mounting groove, and a hollow mounting cavity (1022) is provided between every two sets of the limiting interlayer blocks (1023).

9. A metal-ceramic composite substrate according to claim 8, characterized in that, The arc-shaped positioning plate (1032) and the locking strip (1034) are both inserted into the hollow mounting cavity (1022), and the limiting interlayer block (1023) is inserted into the transition plate (1033).

10. A processing method for a metal-ceramic composite substrate, used to process the metal-ceramic composite substrate as described in claim 9, characterized in that, Includes the following steps: S1. The metal and ceramic blanks are pretreated and machined to cut arc-shaped positioning plates (1032) and locking strips (1034) on multiple sets of transition plates (1033) arranged in a whole. Then, the arc-shaped positioning plates (1032) and locking strips (1034) are inserted into the hollow mounting cavity (1022). S2. Place a transition layer (103) between every two ceramic blanks and the metal, and stack them in pairs. Then, place the activated ceramic blanks, the metal, and the transition layer (103) into a graphite mold and coat them with boron nitride lubricant. S3. The ceramic blank is heated to form a densified material. After being molded by applying pressure, the metal-ceramic composite substrate (1) is placed and kept warm. After the metal-ceramic plate cools down to room temperature, the composite substrate is demolded.

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