A method for manufacturing a copper clad ceramic substrate

Abstract

The embodiment of the present specification mainly relates to the technical field of copper-clad ceramic substrate, in particular to a manufacturing method of copper-clad ceramic substrate, comprising the following steps: S11. obtaining a copper foil layer; S12. obtaining a ceramic substrate, and opening a first through slot on the ceramic substrate to obtain a first ceramic substrate; S13. obtaining a ceramic substrate, and opening a second through slot on the ceramic substrate to obtain a second ceramic substrate; S21. setting a first solder layer on the opposite surface of the first ceramic substrate opening the first through slot; S22. setting a second solder layer on the surface of the second ceramic substrate opening the second through slot; S31. stacking the copper foil layer and the first ceramic substrate and the second ceramic substrate from top to bottom to form a to-be-welded assembly. The manufacturing method of copper-clad ceramic substrate of the present specification can not only improve the heat dissipation effect of the copper-clad ceramic substrate without affecting the warpage value of the copper-clad ceramic substrate by cooperating the copper foil layer, the first ceramic substrate and the second ceramic substrate to form the copper-clad ceramic substrate.

Description

TECHNICAL FIELD

[0001] The embodiment of the present specification mainly relates to the technical field of copper-clad ceramic substrate, in particular to a manufacturing method of copper-clad ceramic substrate. BACKGROUND

[0002] The copper-clad ceramic substrate is an electronic base material made by using the DCB (Direct Copper Bond) technology to sinter the copper foil directly on the ceramic surface. The copper-clad ceramic substrate has excellent thermal cycle performance, shape stability, good rigidity, high thermal conductivity, high reliability, and the copper-clad surface can be etched to various patterns, which can be used in semiconductor refrigerators, electronic heaters, high-power power semiconductor modules and other industrial electronic fields.

[0003] As shown in Figure 1 The existing copper-clad ceramic substrate mostly includes a ceramic substrate, a copper foil layer covering the top surface of the ceramic substrate, and a copper foil layer covering the bottom surface of the ceramic substrate. The copper-clad ceramic substrate with this structure has poor heat dissipation effect. Especially for high-power modules with high heat dissipation requirements, the copper-clad ceramic substrate with this structure may not meet the heat dissipation requirements.

[0004] Therefore, the prior art proposes to open micro-channels in the copper foil layer on the bottom surface to improve the heat dissipation effect of the copper-clad ceramic substrate. However, the copper-clad ceramic substrate with this structure will greatly increase the warpage value. SUMMARY

[0005] The embodiment of the present specification proposes a manufacturing method of copper-clad ceramic substrate to solve the problems existing in the prior art, so that the copper-clad ceramic substrate made thereby can effectively improve the heat dissipation effect without affecting the warpage value.

[0006] The embodiment of the present specification provides a manufacturing method of copper-clad ceramic substrate, including the following steps:

[0007] S11. Obtain a copper foil layer;

[0008] S12. Obtain a ceramic substrate, and open a first through slot on the ceramic substrate to obtain a first ceramic substrate;

[0009] S13. Obtain a ceramic substrate, and open a second through slot on the ceramic substrate to obtain a second ceramic substrate;

[0010] S21. Provide a first solder layer on the opposite surface of the first ceramic substrate where the first through slot is opened;

[0011] S22. Provide a second solder layer on the surface of the second ceramic substrate where the second through slot is opened;

[0012] S31. Stack the copper foil layer and the first ceramic substrate and the second ceramic substrate from top to bottom to form a to-be-welded assembly; wherein the first through groove of the first ceramic substrate of the to-be-welded assembly and the second through groove of the second ceramic substrate of the to-be-welded assembly are connected to form a cooling water channel;

[0013] S32. Weld the to-be-welded assembly.

[0014] Preferably, S12 specifically comprises: engraving the first through groove on the bottom surface of the ceramic substrate by a precision engraving machine;

[0015] The first through groove comprises a plurality of first straight groove portions and a plurality of first curved groove portions, a first curved groove portion connects two adjacent first straight groove portions, the first straight groove portion at the first end of the length direction of the first through groove penetrates the side of the first ceramic substrate to form a first slot opening A1, and the first straight groove portion at the second end of the length direction of the first through groove penetrates the side of the first ceramic substrate to form a first slot opening B1.

[0016] Preferably, S13 specifically comprises: engraving the second through groove on the top surface of the ceramic substrate by a precision engraving machine;

[0017] The second through groove comprises a plurality of second straight groove portions and a plurality of second curved groove portions, a second curved groove portion connects two adjacent second straight groove portions, the second straight groove portion at the first end of the length direction of the second through groove penetrates the side of the second ceramic substrate to form a second slot opening A2, and the second straight groove portion at the second end of the length direction of the second through groove penetrates the side of the second ceramic substrate to form a second slot opening B2.

[0018] Preferably, the thickness of the ceramic substrate obtained in S12 is 0.5-1 mm;

[0019] The thickness of the ceramic substrate obtained in S13 is 0.5-1 mm.

[0020] Preferably, the height of the first through groove is 0.7 times the thickness of the first ceramic substrate; the width of the first through groove is the same as the thickness of the first ceramic substrate;

[0021] The height of the second through groove is 0.7 times the thickness of the second ceramic substrate; the width of the second through groove is the same as the thickness of the second ceramic substrate.

[0022] Preferably, the cross section of the first through groove is rectangular; the cross section of the second through groove is rectangular.

[0023] Preferably, after S13 and before S21, the following steps are further included:

[0024] L11. Clean and dry the copper foil layer:

[0025] The copper foil layer is soaked in 4.5-5.5 wt% dilute sulfuric acid for 2-4 min, and then cleaned by three-stage countercurrent cleaning with pure water, the total time of three-stage countercurrent cleaning is >60 s, and the temperature of pure water during cleaning is room temperature; and the cleaned copper foil layer is dried at a drying temperature of 100℃±10℃.

[0026] L12. The first ceramic substrate and the second ceramic substrate are cleaned and dried:

[0027] The first ceramic substrate and the second ceramic substrate are soaked in 9-11.5 wt% dilute nitric acid for 120-160 min, and then cleaned by three-stage countercurrent cleaning with pure water, each stage of cleaning lasts for 30 s, and the temperature of pure water during cleaning is room temperature; and the cleaned first ceramic substrate and second ceramic substrate are dried at a drying temperature of 100℃±10℃.

[0028] Preferably, S21 specifically comprises: printing a first solder layer on the opposite surface of the first ceramic substrate where the first through slot is formed by a silk screen printing method;

[0029] S22 specifically comprises: printing a second solder layer on the surface of the second ceramic substrate where the second through slot is formed by a silk screen printing method, and the second solder layer does not cover the second through slot.

[0030] Preferably, after S22 and before S31, the following steps are further included:

[0031] L21. The first ceramic substrate provided with the first solder layer and the second ceramic substrate provided with the second solder layer are dried at a drying temperature of 100℃±10℃.

[0032] Preferably, S32 specifically comprises: placing the assembly to be welded into a vacuum brazing furnace, controlling the vacuum degree in the furnace to be between 0.0008-0.01 Pa, controlling the temperature in the furnace to be between 750-950℃, and the welding time is 60-90 min.

[0033] Advantages

[0034] The method for manufacturing the copper-clad ceramic substrate according to the embodiments of the present specification forms the copper-clad ceramic substrate through the cooperation of the copper foil layer, the first ceramic substrate and the second ceramic substrate, which not only improves the heat dissipation effect of the copper-clad ceramic substrate but also does not affect the warpage value of the copper-clad ceramic substrate. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of the copper-clad ceramic substrate in the prior art;

[0036] Figure 2 It is a structural schematic diagram of the copper-clad ceramic substrate provided by the embodiments of the present specification;

[0037] Figure 3 A partial structure schematic diagram of a copper-clad ceramic substrate provided for an embodiment of the present specification is shown in the following figure.

[0038] Figure 4 A structure schematic diagram of a second ceramic substrate provided for an embodiment of the present specification is shown in the following figure. DETAILED DESCRIPTION

[0039] Embodiments of the present specification will be described in more detail below with reference to the accompanying drawings.

[0040] Embodiment 1:

[0041] A manufacturing method of a copper-clad ceramic substrate includes the following steps:

[0042] S11. Obtain a copper foil layer.

[0043] S12. Obtain a ceramic substrate, and open a first through slot on the ceramic substrate to obtain a first ceramic substrate.

[0044] S13. Obtain a ceramic substrate, and open a second through slot on the ceramic substrate to obtain a second ceramic substrate.

[0045] The present embodiment does not limit the sequence of steps S11, S12 and S13.

[0046] The copper-clad ceramic substrate manufactured by the manufacturing method of the copper-clad ceramic substrate of the present embodiment includes, as shown in the following figures, Figure 2 and Figure 3 a copper foil layer 1, a first ceramic substrate 3 and a second ceramic substrate 4 arranged in sequence from top to bottom.

[0047] The first ceramic substrate 3 is connected with the bottom surface of the copper foil layer 1, and the bottom surface of the first ceramic substrate 3 is provided with a first through slot penetrating the side of the first ceramic substrate 3.

[0048] The second ceramic substrate 4 is connected with the bottom surface of the first ceramic substrate 3, and the top surface of the second ceramic substrate 4 is provided with a second through slot penetrating the side of the second ceramic substrate 4, and the second through slot is connected with the first through slot to form a cooling water channel 5.

[0049] The present embodiment removes the bottom copper foil layer in the prior art, and then adds the second ceramic substrate 4.

[0050] Firstly, the first through groove is formed on the first ceramic substrate 3, the second through groove is formed on the second ceramic substrate 4, and the cooling water channel 5 formed by the second through groove and the first through groove is used for heat dissipation. The cooling water channel 5 of the embodiment not only flows through the second ceramic substrate 4, but also flows through the first ceramic substrate 3. Compared with the case that the cooling water channel is directly arranged in the bottom copper foil layer, the heat dissipation effect of the copper clad ceramic substrate is slightly improved. Compared with the copper clad ceramic substrate without the cooling water channel, the heat dissipation effect is effectively improved.

[0051] Secondly, the bottom copper foil layer is arranged in the prior art to prevent the copper clad ceramic substrate from warping. However, the inventors of the present application find that the second ceramic substrate 4 arranged below the first ceramic substrate 3 can also prevent the copper clad ceramic substrate from warping. When the thickness of the second ceramic substrate 4 is a suitable value, the anti-warping effect is better than that of the bottom copper foil layer. That is, when the bottom of the copper clad ceramic substrate is the copper foil layer, and the cooling water channel is arranged in the bottom copper foil layer, the copper clad ceramic substrate has a serious warping phenomenon. In the embodiment, the second ceramic substrate 4 is arranged, and even if the second ceramic substrate 4 is arranged with the second through groove, when the thickness of the second ceramic substrate 4 is suitable, the copper clad ceramic substrate formed by the second ceramic substrate 4, the first ceramic substrate 3 and the copper foil layer 1 has a significantly reduced warping degree value.

[0052] In summary, the copper clad ceramic substrate formed by the copper foil layer 1, the first ceramic substrate 3 and the second ceramic substrate 4 can not only improve the heat dissipation effect of the copper clad ceramic substrate, but also will not affect the warping degree value.

[0053] Further, the step S12 of the embodiment specifically includes: carving the first through groove on the bottom surface of the ceramic substrate by the precision carving machine;

[0054] The first through groove of the first ceramic substrate 3 includes a plurality of first straight groove portions and a plurality of first curved groove portions. A first curved groove portion connects two adjacent first straight groove portions. The first straight groove portion at the first end of the length direction of the first through groove penetrates the side of the first ceramic substrate to form a first slot A1. The first straight groove portion at the second end of the length direction of the first through groove penetrates the side of the first ceramic substrate to form a first slot B1.

[0055] The step S13 of the embodiment specifically includes: carving the second through groove on the top surface of the ceramic substrate by the precision carving machine;

[0056] As Figure 4As shown, the second through groove of the second ceramic substrate 4 includes a plurality of second straight groove portions 41 and a plurality of second curved groove portions 42, a second curved groove portion 42 connects two adjacent second straight groove portions 41, and the second straight groove portion 41 at the first end of the length direction of the second through groove penetrates the side of the second ceramic substrate 4 to form a second slot A2, and the second straight groove portion 41 at the second end of the length direction of the second through groove penetrates the side of the second ceramic substrate 4 to form a second slot B2. The first slot A1 and the second slot A2 are connected to form the water inlet of the cooling water channel 5; the first slot B1 and the second slot B2 are connected to form the water outlet of the cooling water channel 5.

[0057] The specific shape of the first through groove in this embodiment is the same as that of the second through groove. The second ceramic substrate 4 of this embodiment is provided with only one second through groove, so that the entire copper-clad ceramic substrate has only one second slot A2 (i.e. only one water inlet in the end) and one second slot B2 (i.e. only one water outlet in the end), so that the copper-clad ceramic substrate only needs to be connected with one water inlet and one water outlet of the circulating water supply device, and the assembly is more convenient.

[0058] As shown, Figure 4 The second through groove of this embodiment includes a plurality of second straight groove portions 41 arranged in parallel, for example, 9 second straight groove portions 41 arranged in parallel, adjacent second straight groove portions 41 are connected by second curved groove portions 42, and the top view angle of the second curved groove portion 42 is a semicircular ring. The second straight groove portion 41 has a large number of uniform distribution on the second ceramic substrate 4, so that the cooling medium can flow through the entire second ceramic substrate 4, and the heat dissipation effect of the second ceramic substrate 4 is very good.

[0059] The cross section of the second through groove of this embodiment (the cross section perpendicular to the second straight groove portion 41 or the cross section perpendicular to the second curved groove portion 42) is rectangular, and the second through groove with this shape can be more easily engraved on the second ceramic substrate 4.

[0060] Further, the thickness of the ceramic substrate obtained in step S12 of this embodiment is 0.5-1 mm, i.e. the thickness of the first ceramic substrate 3 is 0.5-1 mm. The thickness of the ceramic substrate obtained in step S13 is 0.5-1 mm, i.e. the thickness of the second ceramic substrate 4 is 0.5-1 mm.

[0061] In addition, the height of the first through groove in this embodiment is 0.7 times the thickness of the first ceramic substrate, and the width of the first through groove is the same as the thickness of the first ceramic substrate. The height of the second through groove is 0.7 times the thickness of the second ceramic substrate, and the width of the second through groove is the same as the thickness of the second ceramic substrate.

[0062] Specifically, the thickness of the first ceramic substrate 3 can be 0.63 mm, the height of the first through slot can be 0.45 mm, and the width of the first through slot can be 0.63 mm. The thickness of the second ceramic substrate 4 can be 0.63 mm, the height of the second through slot can be 0.45 mm, and the width of the second through slot can be 0.63 mm.

[0063] Alternatively, the thickness of the first ceramic substrate 3 can be 1 mm, the height of the first through slot can be 0.7 mm, and the width of the first through slot can be 1 mm. The thickness of the second ceramic substrate 4 can be 1 mm, the height of the second through slot can be 0.7 mm, and the width of the second through slot can be 1 mm.

[0064] The thickness of the conventional ceramic substrate is generally 0.32 mm, 0.36 mm, 0.63 mm, 1 mm, etc. In order to make the copper-clad ceramic substrate simple, the ceramic substrate of the existing specification can be directly used in the embodiment. However, in order to set the through slot and to ensure the warping value, the thickness of the ceramic substrate needs to be ensured. Therefore, the ceramic substrate with a thickness of 0.63 mm or 1 mm can be directly used in the embodiment, that is, the thickness of the first ceramic substrate 3 and the second ceramic substrate 4 can both be 0.63 mm, or the thickness of the first ceramic substrate 3 and the second ceramic substrate 4 can both be 1 mm.

[0065] In addition, the inventor of the present application found that when the height of the through slot is about 0.7 times the thickness of the ceramic substrate and when the width of the through slot is the same as the thickness of the ceramic substrate, the cooling water flow in the cooling water channel 5 can efficiently take away the heat on the copper-clad ceramic substrate, and the warping phenomenon of the copper-clad ceramic substrate can be well prevented.

[0066] The method for manufacturing the copper-clad ceramic substrate of the embodiment further includes the following steps:

[0067] S21. A first solder layer is arranged on the opposite surface of the first ceramic substrate where the first through slot is formed.

[0068] S22. A second solder layer is arranged on the surface of the second ceramic substrate where the second through slot is formed.

[0069] S31. The copper foil layer and the first ceramic substrate and the second ceramic substrate are stacked from top to bottom to form a to-be-soldered assembly; wherein the first through slot of the first ceramic substrate of the to-be-soldered assembly is connected with the second through slot of the second ceramic substrate of the to-be-soldered assembly to form a cooling water channel.

[0070] S32. The to-be-soldered assembly is soldered.

[0071] The embodiment does not limit the sequence of steps S21 and S22.

[0072] The copper-clad ceramic substrate prepared by the method of manufacturing the copper-clad ceramic substrate of the embodiment, as shown in Figure 3 The first solder layer 6 and the second solder layer 7 are printed on the opposite surfaces of the first ceramic substrate and the second ceramic substrate by the screen printing method. The screen printing is performed at a temperature of 20±10℃ and a humidity of ≤60%RH.

[0073] The method of manufacturing the copper-clad ceramic substrate of the embodiment further comprises the following steps after step S13 and before step S21:

[0074] L11. Cleaning and drying the copper foil layer:

[0075] The copper foil layer 1 is soaked in 4.5-5.5wt% dilute sulfuric acid for 2-4min, and then cleaned by three-stage countercurrent cleaning with pure water. The total time of the three-stage countercurrent cleaning is >60s, and the temperature of the pure water is room temperature during the cleaning. The cleaned copper foil layer 1 is dried at a drying temperature of 100℃±10℃. The thickness of the copper foil layer 1 is not limited in the embodiment, and can be selected according to the actual use requirement.

[0076] L12. Cleaning and drying the first ceramic substrate and the second ceramic substrate:

[0077] The first ceramic substrate 3 and the second ceramic substrate 4 are soaked in 9-11.5wt% dilute nitric acid for 120-160min, and then cleaned by three-stage countercurrent cleaning with pure water. Each stage of cleaning lasts for 30s, and the temperature of the pure water is room temperature during the cleaning. The cleaned first ceramic substrate 3 and the second ceramic substrate 4 are dried at a drying temperature of 100℃±10℃.

[0078] The sequence of steps L11 and L12 is not limited in the embodiment. The steps L11 and L12 are provided to make the subsequent setting of the first solder layer and the second solder layer better.

[0079] The method of manufacturing the copper-clad ceramic substrate of the embodiment further comprises the following steps after step S22 and before step S31:

[0080] L21. The first ceramic substrate 3 provided with the first solder layer 6 and the second ceramic substrate 4 provided with the second solder layer 7 are dried at a drying temperature of 100℃±10℃. The thickness of the first solder layer 6 and the second solder layer 7 in the embodiment can be 30±5μm. The step L21 is provided to make the subsequent vacuum brazing of the first solder layer and the second solder layer better.

[0081] The step S32 in the embodiment specifically includes: placing the to-be-welded assembly into a vacuum brazing furnace, controlling the vacuum degree in the furnace to be between 0.0008 and 0.01 Pa, controlling the temperature in the furnace to be between 750 and 950 ℃, and the welding time being 60 to 90 min.

[0082] After the second solder layer 7 is printed on the top surface of the second ceramic substrate 4 (i.e. the surface with the second through groove) and the first solder layer 6 is printed on the top surface of the first ceramic substrate 3 (i.e. the surface without the first through groove), the first ceramic substrate 3 and the second ceramic substrate 4 are first dried.

[0083] After the first ceramic substrate 3 and the second ceramic substrate 4 are dried, the copper foil layer 1, the first ceramic substrate 3 and the second ceramic substrate 4 are then stacked in sequence from top to bottom to form the to-be-welded assembly. Then the to-be-welded assembly is placed into a vacuum brazing furnace, the vacuum degree in the furnace is controlled to be between 0.0008 and 0.01 Pa, and the temperature in the furnace is controlled to be between 750 and 950 ℃. At the beginning, the temperature in the furnace is relatively low, and when the temperature in the furnace rises to between 750 and 950 ℃, the first solder layer 6 and the second solder layer 7 begin to melt. The melted first solder layer 6 and the second solder layer 7 fill the entire weld joint through capillary flow, so as to realize the welding of the copper foil layer 1 and the first ceramic substrate 3 and the welding of the first ceramic substrate 3 and the second ceramic substrate 4.

[0084] Firstly, the vacuum brazing can make the first solder layer 6 and the second solder layer 7 have fewer cavities, so that the heat transfer effect of the copper-clad ceramic substrate is better, and thus the heat dissipation effect of the copper-clad ceramic substrate is better.

[0085] Secondly, the vacuum brazing can make the connection between the first ceramic substrate 3 and the second ceramic substrate 4 have better sealing performance, so that the cooling medium in the cooling water channel 5 will not leak, and thus the copper-clad ceramic substrate can be used for a long time and will not be scrapped due to the leakage of the cooling medium.

[0086] In summary, the first solder layer 6 is used to vacuum-brazing connect the copper foil layer 1 and the first ceramic substrate 3, and the second solder layer 7 is used to vacuum-brazing connect the first ceramic substrate 3 and the second ceramic substrate 4, so that the weld joint between the copper foil layer 1 and the first ceramic substrate 3 and the weld joint between the first ceramic substrate 3 and the second ceramic substrate 4 have fewer cavities and better sealing performance, and thus the heat transfer effect of the copper-clad ceramic substrate is good and the cooling medium will not leak, and finally the heat dissipation effect of the copper-clad ceramic substrate is better and the service life is longer.

[0087] After the step S32 is completed, the basic copper-clad ceramic substrate is completed. Then the following steps can be further performed:

[0088] L31. The copper-clad ceramic substrate after welding is soaked in 9-11.5wt% dilute nitric acid for 60-90min, and then cleaned with pure water in three sections of countercurrent, each section of cleaning time is 30s, and the temperature of pure water is room temperature during cleaning.

[0089] L32. The copper-clad ceramic substrate after acid water cleaning is sprayed with a protective layer, and the copper-clad ceramic substrate after spraying is placed in an exposure machine for exposure to expose the copper foil layer to the desired pattern.

[0090] L33. The copper-clad ceramic substrate after exposure is developed.

[0091] L34. The copper-clad ceramic substrate after development is etched to etch the copper foil layer to the desired pattern.

[0092] L35. The copper-clad ceramic substrate after etching is deformed.

[0093] L36. The copper-clad ceramic substrate after deforming is subjected to solder layer etching.

[0094] L37. The water supply inlet of the circulating water supply device is connected to the water inlet of the cooling water channel 5, and the water supply outlet of the circulating water supply device is connected to the water outlet of the cooling water channel 5.

[0095] L38. The chip 2 is welded with the copper foil layer 1.

[0096] Through steps L31-L38, a power module can be made, and the copper-clad ceramic substrate of the power module is formed by cooperation of the copper foil layer 1, the first ceramic substrate 3 and the second ceramic substrate 4, which not only improves the heat dissipation effect of the copper-clad ceramic substrate (i.e. the power module) and does not affect the warpage value of the copper-clad ceramic substrate.

[0097] Although the drawings show certain embodiments of the present specification, it should be understood that the present specification can be implemented in various forms, and should not be interpreted as being limited to the embodiments set forth herein, but rather these embodiments are provided to more thoroughly and completely understand the present specification. It should be understood that the drawings and embodiments of the present specification are only for exemplary purposes, and are not intended to limit the scope of protection of the present specification.

Claims

1. A method for manufacturing a copper-clad ceramic substrate, characterized in that, Includes the following steps: S11. Obtain the copper foil layer; S12. Obtain a ceramic substrate and open a first through groove on the ceramic substrate to obtain a first ceramic substrate; S13. Obtain a ceramic substrate and form a second through groove on the ceramic substrate to obtain a second ceramic substrate; S21. A first solder layer is formed on the surface opposite to the first through groove in the first ceramic substrate; S22. A second solder layer is formed on the surface of the second ceramic substrate where the second through groove is formed; S31. The copper foil layer, the first ceramic substrate, and the second ceramic substrate are stacked from top to bottom to form a component to be welded; wherein, the first through groove of the first ceramic substrate of the component to be welded is connected with the second through groove of the second ceramic substrate of the component to be welded to form a cooling water channel. S32. Weld the components to be welded; S12 specifically includes: carving a first through groove on the bottom surface of the ceramic substrate using a precision engraving machine; The first through groove includes a plurality of first straight groove portions and a plurality of first curved groove portions. One first curved groove portion connects two adjacent first straight groove portions, and the first straight groove portion located at the first end in the length direction of the first through groove penetrates the side of the first ceramic substrate to form a first groove A1. The first straight groove portion located at the second end in the length direction of the first through groove penetrates the side of the first ceramic substrate to form a first groove B1. S13 specifically includes: carving a second through groove on the top surface of the ceramic substrate using a precision engraving machine; The second through groove includes a plurality of second straight groove portions and a plurality of second curved groove portions. One second curved groove portion connects two adjacent second straight groove portions, and the second straight groove portion located at the first end in the length direction of the second through groove penetrates the side of the second ceramic substrate to form a second groove A2. The second straight groove portion located at the second end in the length direction of the second through groove penetrates the side of the second ceramic substrate to form a second groove B2. The thickness of the ceramic substrate obtained in S12 is 0.5 to 1 mm; The thickness of the ceramic substrate obtained in S13 is 0.5 to 1 mm; The height of the first through groove is 0.7 times the thickness of the first ceramic substrate; the width of the first through groove is the same as the thickness of the first ceramic substrate. The height of the second through groove is 0.7 times the thickness of the second ceramic substrate; the width of the second through groove is the same as the thickness of the second ceramic substrate.

2. The method for manufacturing a copper-clad ceramic substrate according to claim 1, characterized in that, The first through groove has a rectangular cross-section; the second through groove has a rectangular cross-section.

3. The method for manufacturing a copper-clad ceramic substrate according to claim 1, characterized in that, The following steps are included after S13 and before S21: L11. Clean and dry the copper foil layer: The copper foil layer was soaked in 4.5-5.5 wt% dilute sulfuric acid for 2-4 minutes, and then rinsed with pure water in three countercurrent stages. The total time of the three countercurrent stages was >60 seconds. The temperature of the pure water during the rinsing was room temperature. The cleaned copper foil layer was then dried at a drying temperature of 100℃±10℃. L12. Clean and dry the first and second ceramic substrates: The first and second ceramic substrates were soaked in 9-11.5 wt% dilute nitric acid for 120-160 min, and then rinsed with pure water in three countercurrent stages, each stage lasting 30 s. The temperature of the pure water was room temperature during the rinsing. The cleaned first and second ceramic substrates were then dried at a drying temperature of 100℃±10℃.

4. The method for manufacturing a copper-clad ceramic substrate according to claim 1, characterized in that, S21 specifically includes: printing a first solder layer on the surface opposite to the first through groove on the first ceramic substrate by screen printing; S22 specifically includes: printing a second solder layer on the surface of the second ceramic substrate where the second through groove is formed by screen printing, wherein the second solder layer does not cover the second through groove.

5. The method for manufacturing a copper-clad ceramic substrate according to claim 1, characterized in that, The following steps are included after S22 and before S31: L21. Dry the first ceramic substrate with the first solder layer and the second ceramic substrate with the second solder layer at a drying temperature of 100℃±10℃.

6. The method for manufacturing a copper-clad ceramic substrate according to claim 1, characterized in that, S32 specifically includes: placing the component to be welded into a vacuum brazing furnace, controlling the vacuum level in the furnace between 0.0008 and 0.01 Pa, controlling the temperature in the furnace between 750 and 950°C, and the welding time between 60 and 90 minutes.

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