Metal and ceramic substrate integration method, substrate structure and packaging structure

Abstract

The invention provides an integration method of a metal substrate and a ceramic substrate, a substrate structure and a packaging structure. The integration method comprises the following steps: carrying out surface treatment on a ceramic substrate raw material and cutting the ceramic substrate raw material into an initial ceramic substrate according to a preset first specification; performing surface treatment on the metal sheet raw material and cutting the metal sheet raw material into initial metal sheets according to a preset second specification; a plurality of initial ceramic substrates and initial metal sheets are sequentially stacked and pressed in an alternate and spaced mode, and a combination of the ceramic substrates and the metal sheets is obtained; sintering the combined body to form an MCMI mother board; the MCMI mother board is cut according to a preset third specification, and first MCMI sheets with the same layer number as the MCMI mother board are obtained; grinding and polishing the first MCMI sheet to obtain a pretreated MCMI sheet; and carrying out surface metallization treatment on the pretreated MCMI sheet to obtain the MCMI substrate. When the MCMI substrate, namely the multilayer ceramic metal integrated substrate, is applied to a packaging structure, the number of interface layers in the packaging structure can be reduced, and the heat dissipation effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of substrates used for power electronics and microelectronics packaging, and in particular to an integration method of metal and ceramic substrates, a substrate structure and a packaging structure. Background Art

[0002] The metallized ceramic substrates used in traditional packaging of power electronic devices and high-power LEDs are mainly planar structures. The heat generated by the chip is transmitted to the heat sink through the metallized ceramic substrate and dissipated into the surrounding environment. Traditional metallized ceramic substrates mainly include DBC, DBA, AMB, DPC substrates, etc. In the traditional packaging structure, the heat generated by the chip needs to pass through the brazing layer, metallized ceramic substrate, brazing layer in sequence, and finally be conducted to the heat sink. More interface layers in the heat dissipation path will bring greater thermal resistance, which is not conducive to the rapid dissipation of the heat generated by the chip. The accumulated heat will cause the junction temperature to rise.

[0003] For power electronic devices, Figure 1 As shown in the figure, the heat generated by the chip passes through a brazing layer, then through DBC or DBA or AMB, and then through another brazing layer, and finally transferred to the heat sink, and dissipated to the surrounding environment through active or passive methods. The entire heat transfer path needs to pass through about 6 layers of interface layers before it can reach the heat sink smoothly. In addition, if the ceramic is directly sintered or welded on the heat sink in order to reduce thermal resistance, this structure will cause serious deformation of the heat sink and ceramic, especially when the thick copper is directly sintered on the ceramic substrate using the DBC process. The overall warping deformation is so serious that it cannot be used. Even after the correction process, the reliability will be poor if it is barely used.

[0004] For high-power LEDs, Figure 2 As shown in the figure, the heat generated by the chip first passes through a brazing layer, then through a DPC substrate, then through a brazing layer, and then reaches the copper layer heat sink, and finally through another brazing layer before it can be transferred to the heat sink. After active or passive heat dissipation, the heat is dissipated to the surrounding environment. The entire heat transfer path needs to pass through 6 layers of thermal resistance before it can finally reach the heat sink (aluminum substrate or copper substrate). In addition, in high-power LED packaging, flip chip packaging (FC packaging) or traditional packaging is more commonly used. The spacing between the two electrodes of the chip is generally less than 200 microns. If conventional DBC, DBA, AMB processes are used, it is difficult to meet the minimum line spacing requirement of 200 microns. Therefore, DPC can only be used to thicken the copper layer to about 100 microns to ensure a line spacing of 200 microns. However, the thermal conductivity of a copper layer with a thickness of 100 microns is poor.

[0005] Therefore, a technical solution is needed to improve the heat dissipation effect of a packaging structure. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides an integration method of metal and ceramic substrates, a substrate structure and a packaging structure. When the MCMI substrate, i.e., a multilayer ceramic-metal integrated substrate, obtained by the integration method of metal and ceramic substrates is used in a packaging structure, the number of interface layers in the packaging structure can be reduced and the heat dissipation effect can be improved.

[0007] The first method for integrating a metal and a ceramic substrate provided by the present invention comprises the following specific steps:

[0008] Surface treating the ceramic substrate raw material and cutting it into initial ceramic substrates according to a preset first specification;

[0009] Surface treating the metal sheet raw material and cutting it into initial metal sheets according to a preset second specification;

[0010] Stacking and pressing a plurality of the initial ceramic substrates and the initial metal sheets in an alternating manner to obtain a combination of the ceramic substrates and the metal sheets;

[0011] Sintering the assembly to form a MCMI motherboard;

[0012] Cutting the MCMI motherboard according to a preset third specification to obtain a first MCMI sheet having the same number of layers as that of the MCMI motherboard;

[0013] Grinding and polishing the first MCMI sheet to obtain a pretreated MCMI sheet;

[0014] The pre-treated MCMI sheet is subjected to surface metallization treatment to obtain a MCMI substrate.

[0015] In a possible implementation, in the first method for integrating metal and ceramic substrates, when surface treating the ceramic substrate raw material, a ceramic substrate surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

[0016] In a possible implementation, in the first method for integrating metal and ceramic substrates, when surface treating the metal sheet raw material, the metal sheet surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

[0017] The present invention also provides a first substrate structure, which is manufactured by the above-mentioned integration method of the first metal and ceramic substrate.

[0018] The present invention also provides a first packaging structure, which is obtained based on the packaging of the first substrate structure mentioned above.

[0019] The second method for integrating a metal and a ceramic substrate provided by the present invention comprises the following specific steps:

[0020] Surface treating the ceramic substrate raw material and cutting it into initial ceramic substrates according to a preset first specification;

[0021] Surface treating the metal sheet raw material and cutting it into initial metal sheets according to a preset second specification;

[0022] Stacking and pressing a plurality of the initial ceramic substrates and the initial metal sheets in an alternating manner to obtain a combination of the ceramic substrates and the metal sheets;

[0023] Sintering the assembly to form a MCMI motherboard;

[0024] Cutting the MCMI motherboard according to a preset third specification to obtain a first MCMI sheet having the same number of layers as that of the MCMI motherboard;

[0025] Combining and sintering at least two of the first MCMI sheets together to obtain a second MCMI sheet;

[0026] Grinding and polishing the second MCMI sheet to obtain a pretreated MCMI sheet;

[0027] The pre-treated MCMI sheet is subjected to surface metallization treatment to obtain a MCMI substrate.

[0028] In a possible implementation, in the second method for integrating metal and ceramic substrates, when surface treating the raw material of the ceramic substrate, a surface treatment method of the ceramic substrate is selected according to the process required for sintering the assembly and the specific material of the raw material of the ceramic substrate.

[0029] In a possible implementation, in the second method for integrating metal and ceramic substrates, when surface treating the metal sheet raw material, the metal sheet surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

[0030] The present invention also provides a second substrate structure, which is manufactured by the above-mentioned second metal and ceramic substrate integration method.

[0031] The present invention also provides a second packaging structure, which is obtained based on the packaging of the second substrate structure as described above.

[0032] The technical solution provided by the present invention has at least the following beneficial effects:

[0033] 1. The MCMI substrate of the present invention can meet the requirements of narrow line spacing of high-power LEDs, especially the requirements of Flip-ChiP packaging with narrow line spacing and high heat dissipation;

[0034] 2. The MCMI substrate of the present invention can reduce the packaging thermal resistance interface of power electronic devices from 6 layers to 4 layers, significantly improving the heat dissipation performance;

[0035] 3. The MCMI substrate of the present invention can be used to arbitrarily combine various types and orientations to achieve various signal interconnections, which is very suitable for high-density 3D interconnect packaging and can partially replace high-density interconnect substrates (HDI), low-temperature co-fired ceramic substrates (LTCC), and high-temperature co-fired ceramic substrates (HTCC);

[0036] 4. The MCMI substrate of the present invention can realize any design of thermal expansion coefficient between metal and ceramic;

[0037] 5. By using the MCMI substrate of the present invention, the DBC substrate can be directly sintered on the MCMI, which reduces the thermal resistance interface without any deformation, and significantly improves the reliability of the power electronic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of a typical packaging structure of a power electronic device;

[0039] Figure 2 A schematic diagram of a typical LED packaging structure;

[0040] Figure 3 A flow chart of a first method for integrating a metal and a ceramic substrate provided by an embodiment of the present invention;

[0041] Figure 4 A flow chart of a second method for integrating a metal and a ceramic substrate provided by an embodiment of the present invention;

[0042] FIG5( a ) is a schematic diagram of ceramic and metal superposition in a MCMI substrate production process provided by an embodiment of the present invention;

[0043] FIG5( b ) is a schematic diagram of sintering a MCMI motherboard in a MCMI substrate production process provided by an embodiment of the present invention;

[0044] FIG5( c ) is a schematic diagram of cutting an MCMI motherboard into MCMI slices in a MCMI substrate production process provided by an embodiment of the present invention;

[0045] FIG5( d ) is a schematic diagram of combined sintering (same orientation) of MCMI sheets in a MCMI substrate production process provided by an embodiment of the present invention;

[0046] FIG5( e ) is a schematic diagram of remetallization of the surface of an MCMI sheet in a MCMI substrate production process provided by an embodiment of the present invention;

[0047] FIG5( f ) is a schematic diagram of the finished product structure after metallization of an MCMI sheet in a MCMI substrate production process provided by an embodiment of the present invention;

[0048] Figure 6 A schematic diagram of sintering a combination of MCMI sheets with different orientations into a functionalized MCMI substrate provided by an embodiment of the present invention;

[0049] FIG. 7( a ) is a schematic diagram of a first packaging structure for reducing an interface thermal resistance layer provided by an embodiment of the present invention;

[0050] FIG7( b ) is a schematic diagram of a second packaging structure for reducing the interface thermal resistance layer provided by an embodiment of the present invention;

[0051] FIG. 7( c ) is a schematic diagram of a third packaging structure for reducing the interface thermal resistance layer provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments are only used to explain the present invention and do not limit the protection scope of the present invention.

[0053] The present invention relates to an MCMI substrate for power electronic devices or high-power LED packaging and a corresponding production process. The multilayer ceramic metal integrated substrate is referred to as the MCMI substrate, which belongs to the field of ceramic surface metallization and functionalization. It should be pointed out that the direct copper-clad ceramic substrate in the present invention is referred to as DBC, the direct aluminum-clad ceramic substrate is referred to as DBA, the active metal brazing is referred to as AMB, and the direct electroplated copper is referred to as DPC. In the DBC technical scheme: the copper sheet is oxidized and placed on the ceramic, and the copper sheet and the ceramic are sintered together at high temperature to obtain the DBC substrate. In the DBA technical scheme: according to the different ceramic materials, a transition metal is introduced or not, and aluminum and ceramic are sintered together under high temperature and protective gas or high vacuum conditions to obtain a DBA substrate. In the AMB technical scheme: the active metal solder is printed on both sides of the ceramic, and then the copper and ceramic are superimposed into a sandwich structure, and the copper and ceramic are sintered together at high temperature to obtain an AMB substrate. In the DPC technical scheme: active metal titanium (Ti) and copper (Cu) are sputtered onto the ceramic surface by magnetron sputtering to form a seed layer, and then the DPC substrate is formed by electroplating thickening. When these substrates obtained by traditional production processes are used in power electronic devices or high-power LED packaging, they have many layers of complex interfaces, especially the introduction of dissimilar metals in the brazing process, which causes excessive thermal resistance and is not conducive to the chip quickly dissipating heat to the surrounding environment. In this regard, the present invention solves the defects of the prior art by constructing a vertical multi-layer ceramic-metal integrated substrate.

[0054] Please refer to Figure 3The first method for integrating a metal and a ceramic substrate provided by the present invention comprises the following specific steps:

[0055] S10: Surface-treating the ceramic substrate raw material and cutting it into initial ceramic substrates according to a preset first specification.

[0056] In this embodiment, the ceramic substrate raw material refers to ceramic substrates of various specifications and thicknesses, including but not limited to alumina ceramic substrates (Al2O3), aluminum nitride ceramic substrates (AlN), silicon nitride ceramic substrates (Si3N4), zirconium oxide doped toughened alumina substrates (ZTA), and quartz glass substrates (SiO2). The first specification is the specification required for actual production, which includes the shape, shape, and perforation in addition to the required substrate size and graphic size. The shape includes but is not limited to a conventional rectangle, and the perforation includes but is not limited to a round hole or a square hole.

[0057] In a possible implementation, in step S10 of the first method for integrating metal and ceramic substrates, when surface treating the ceramic substrate raw material, a ceramic substrate surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

[0058] In this embodiment, when selecting a ceramic substrate surface treatment method for surface treatment, there are the following situations:

[0059] If the DBC process is used when sintering the assembly, and the raw material of the ceramic substrate is Al2O3 ceramic or ZTA ceramic, it is only necessary to clean the surface of the Al2O3 ceramic or ZTA ceramic.

[0060] If the DBC process is used when sintering the assembly, and the raw material of the ceramic substrate is AlN ceramic, it is necessary to modify the surface of the AlN ceramic, generate a transition layer on the ceramic surface, and then clean the surface.

[0061] If the AMB process is used for sintering the assembly, and the raw material of the ceramic substrate is AlN ceramic or Si3N4 ceramic, then after cleaning the surface of the AlN ceramic or Si3N4 ceramic, it is necessary to print active metal solder or welding sheet on the surface of the AlN ceramic or Si3N4 ceramic.

[0062] If the DBA process is to be used when sintering the assembly, a thin transition layer needs to be formed on the ceramic surface.

[0063] S20: Surface-treating the metal sheet raw material and cutting it into initial metal sheets according to a preset second specification.

[0064] In this embodiment, the metal sheet raw material includes but is not limited to copper (Cu), aluminum (Al), nickel (Ni) and alloys thereof. The second specification is the specification required for actual production, which includes the shape, form and perforation in addition to the required metal sheet size and pattern size. The shape includes but is not limited to a conventional rectangle, and the perforation includes but is not limited to a round hole or a square hole.

[0065] In a possible implementation, in step S20 of the first metal and ceramic substrate integration method, when surface treating the metal sheet raw material, the metal sheet surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

[0066] In this embodiment, when the metal sheet surface treatment method is selected for metallization surface treatment, it is divided into the following situations:

[0067] If the DBC process is used when sintering the assembly, the ceramic substrate material is Al2O3 ceramic, AlN ceramic or ZTA ceramic, and the metal sheet material is copper, the copper surface needs to be cleaned and pre-oxidized to form an oxide film on the copper surface. The pre-oxidation here refers to wet oxidation (chemical oxidation) or dry oxidation.

[0068] If the AMB process is used for sintering the assembly, the ceramic substrate raw material uses AlN ceramic, Si3N4 ceramic or ZTA ceramic, and the metal sheet raw material uses copper, then whether to print active metal solder or welding sheet on the copper surface is selected according to whether active metal solder has been printed on the surface of the ceramic substrate raw material.

[0069] If the DBA process is used for sintering the assembly, and the ceramic substrate material is AlN ceramic, Si3N4 ceramic or ZTA ceramic, then whether to form a metal transition layer on the surface of the metal sheet material such as aluminum is selected according to whether there is a metal transition layer on the surface of the ceramic substrate material.

[0070] S30: stacking and pressing a plurality of the initial ceramic substrates and the initial metal sheets in an alternating manner to obtain a combination of the ceramic substrates and the metal sheets.

[0071] In this embodiment, referring to FIG. 5 (a), the initial ceramic substrate is distributed in the form of multiple layers such as ceramic layer 1, ceramic layer 2, ceramic layer 3, ceramic layer 4, etc., and the initial metal sheet is distributed in the form of multiple layers such as metal layer 1, metal layer 2, metal layer 3, metal layer 4, etc., and the two are alternately spaced to realize multi-layer superposition, and a combination of a ceramic substrate and a metal sheet is formed after compaction. It should be noted that the thickness and type of the ceramic substrate and the metal sheet in the combination are not limited to the same ceramic substrate of the same thickness, nor are they limited to the same metal sheet of the same thickness. In the specific implementation, ceramic substrates of different thicknesses and different types, as well as metal sheets of different types and different thicknesses can be matched according to needs to realize sintering of multiple types of multilayer ceramic metal integrated substrates, i.e., MCMI substrates. It should be pointed out that when the multilayer ceramic substrates in the combination are ceramic substrates of different thicknesses and / or different types, the thickness and / or type of the corresponding initial ceramic substrates are also different, and the thickness and / or type of the corresponding ceramic substrate raw materials used to make the initial ceramic substrates are also different. When the multi-layer metal sheets in the assembly are metal sheets of different thicknesses and / or different types, the thicknesses and / or types of the corresponding initial metal sheets are also different, and the thicknesses and / or types of the corresponding metal sheet raw materials used to make the initial metal sheets are also different.

[0072] It should be noted that the size and specifications of the initial ceramic substrate and initial metal sheet used to generate the assembly are not limited, and the size of the initial metal sheet is not limited to the same size as the initial ceramic substrate. The size of the initial metal sheet can be greater than, equal to or smaller than the size of the initial ceramic substrate.

[0073] S40: sintering the assembly to form an MCMI motherboard.

[0074] In this embodiment, referring to FIG. 5( b ), the ceramic layers 1, 2, 3, 4, etc. in the assembly are sintered and integrated with the metal layers 1, 2, 3, 4, etc. to form a whole MCMI motherboard. In the specific implementation, the assembly of the ceramic substrate and the metal sheet is placed in a furnace and sintered to make the metal and the ceramic closely combined to form a motherboard of a multi-layer ceramic metal integrated substrate (MCMI), namely, a MCMI motherboard.

[0075] S50a: Cutting the MCMI motherboard according to a preset third specification to obtain a first MCMI sheet having the same number of layers as that of the MCMI motherboard.

[0076] In this embodiment, referring to FIG. 5( c ), the third specification is a specification determined according to actual implementation needs. In specific implementation, the MCMI motherboard can be cut into a plurality of thin sheets of required specifications, namely, the first MCMI thin sheets, in a horizontal order by laser or mechanical processing. The laser and mechanical processing methods refer to cutting through the MCMI motherboard by laser to form MCMI thin sheets, and the mechanical processing methods refer to cutting by methods including but not limited to water jet, thin grinding wheel (DISCO), diamond wire, etc. In specific cutting, a vertical cutting method can be used. Vertical cutting of the MCMI motherboard means that the thin sheet after cutting has the same thickness and number of layers as the MCMI motherboard. However, the specific cutting method is not limited to vertical cutting, but also includes inclined cutting at a certain angle, so as to form the desired various forms of ceramics and metals spaced apart from each other.

[0077] S60a: Grinding and polishing the first MCMI flake to obtain a pre-treated MCMI flake.

[0078] In this embodiment, the grinding and polishing operations performed on the first MCMI sheet can adopt conventional grinding and polishing methods.

[0079] S70: performing surface metallization treatment on the pre-treated MCMI sheet to obtain a MCMI substrate.

[0080] In this embodiment, referring to FIG. 5( e ) and FIG. 5( f ), the surface metallization can be performed by a conventional surface metallization method. When the pre-treated MCMI sheet is subjected to surface metallization, the surface metallization can be performed in any manner such as single-sided, double-sided, multi-sided, or all-sided. The final MCMI substrate obtained after the surface metallization treatment is a multi-layer ceramic metal integrated substrate with a vertical structure.

[0081] The present invention also provides a first substrate structure, which is manufactured by the above-mentioned integration method of the first metal and ceramic substrate.

[0082] In this embodiment, referring to FIG. 5( f ), the first substrate structure is an MCMI substrate manufactured by the first metal and ceramic substrate integration method, which is a multi-layer ceramic-metal integrated substrate with a vertical structure that can reduce the interface layer and enhance heat dissipation.

[0083] The present invention also provides a first packaging structure, which is obtained based on the packaging of the first substrate structure mentioned above.

[0084] Please refer to Figure 4 The second method for integrating a metal and a ceramic substrate provided by the present invention comprises the following specific steps:

[0085] S10: Surface-treating the ceramic substrate raw material and cutting it into initial ceramic substrates according to a preset first specification.

[0086] S20: Surface-treating the metal sheet raw material and cutting it into initial metal sheets according to a preset second specification.

[0087] S30: stacking and pressing a plurality of the initial ceramic substrates and the initial metal sheets in an alternating manner to obtain a combination of the ceramic substrates and the metal sheets.

[0088] S40: sintering the assembly to form an MCMI motherboard.

[0089] S50a: Cutting the MCMI motherboard according to a preset third specification to obtain a first MCMI sheet having the same number of layers as that of the MCMI motherboard.

[0090] S50b: Sintering at least two of the first MCMI sheets together to obtain a second MCMI sheet.

[0091] In this embodiment, referring to FIG. 5(d) and Figure 6 , and sintering is carried out by a conventional sintering method. In the specific implementation, two or more cut MCMI sheets, i.e., the first MCMI sheets, are combined in an appropriate manner using an appropriate metallization process, and then sintered together to obtain a combination of MCMI sheets, i.e., the second MCMI sheet. The metallization process here can be a DBC, DBA, AMB or other metallization process. The appropriate combination here refers to sintering two or more MCMI sheets, i.e., the first MCMI sheets, with the same or different orientations. The combination method with the same orientation can refer to Figure 5(d), and the combination method with different orientations can refer to Figure 6 .

[0092] S60b: Grinding and polishing the second MCMI flake to obtain a pre-treated MCMI flake.

[0093] In this embodiment, the grinding and polishing operations performed on the second MCMI sheet can adopt conventional grinding and polishing methods.

[0094] S70: performing surface metallization treatment on the pre-treated MCMI sheet to obtain a MCMI substrate.

[0095] In a possible implementation, in the second method for integrating metal and ceramic substrates, when surface treating the raw material of the ceramic substrate, a surface treatment method of the ceramic substrate is selected according to the process required for sintering the assembly and the specific material of the raw material of the ceramic substrate.

[0096] In a possible implementation, in the second method for integrating metal and ceramic substrates, when surface treating the metal sheet raw material, the metal sheet surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

[0097] The present invention also provides a second substrate structure, which is manufactured by the above-mentioned second metal and ceramic substrate integration method.

[0098] In this embodiment, the second substrate structure is an MCMI substrate made by the second metal and ceramic substrate integration method, which is a multi-layer ceramic metal integrated substrate with a vertical structure that can reduce the interface layer and enhance heat dissipation. The second basic structure is similar to the first basic structure, and a specific form of expression is shown in Figure 5(f).

[0099] The present invention also provides a second packaging structure, which is obtained based on the packaging of the second substrate structure as described above.

[0100] In this embodiment, the first packaging structure and the second packaging structure are described together. The first packaging structure is obtained by packaging based on the first substrate structure, and the specific packaging structure will vary depending on the packaging process and the first substrate structure. The second packaging structure is obtained by packaging based on the second substrate structure, and the specific packaging structure will vary depending on the packaging process and the second substrate structure.

[0101] Assuming that the first packaging structure or the second packaging structure is based on an Al2O3-MCMI substrate, i.e., an Al2O3-type MCMI substrate, a specific implementation is as follows:

[0102] S1: 10 alumina ceramic substrates with a size of 127*127*0.20 (mm) were subjected to surface ultrasonic cleaning;

[0103] S2: After ultrasonic cleaning of the surfaces of 11 copper sheets with a size of 127*127*1.50 (mm), the sheets are oxidized under the condition of an oxygen content of 100-200 PPM to form a copper oxide film on the surfaces of the copper sheets;

[0104] S3: stacking the treated alumina ceramic substrate and the copper sheet with oxide film in sequence, placing them in a mold and pressing them tightly so that there is no obvious gap between the alumina ceramic substrate and the copper sheet;

[0105] S4: Using the DBC process, the combination of the alumina ceramic substrate and the copper sheet is placed in a nitrogen-protected tunnel furnace for sintering so that the copper sheet and the alumina ceramic substrate are tightly combined to form an MCMI master (the sintering conditions are: the highest temperature is 1075°C; the holding time is 15 minutes; the oxygen content in the sintering environment furnace is about 100PPM);

[0106] S5: Cut the MCMI master plate horizontally into 127*18.5*3.0 (mm) MCMI sheets by diamond wire method;

[0107] S6: using DBC process to sinter two MCMI sheets into 127*37.0*3.0 (mm) MCMI sheets;

[0108] S7: grinding and polishing the MCMI slice after step S5 or step S6;

[0109] S8: Using the DBC process, a layer of 127*37.0*0.30 (mm) copper sheet is sintered on the upper and lower surfaces of the ground and polished MCMI sheet;

[0110] S9: sintering AlN-DBC on the MCMI substrate by using the DBC process to form an integrated structure of a heat sink and a substrate as shown in FIG. 7( a ), namely, the first packaging structure or the second packaging structure.

[0111] Assuming that the first packaging structure is based on a ZTA-MCMI substrate, i.e., a ZTA-type MCMI substrate, a specific implementation is as follows:

[0112] S1: 15 ZTA ceramic substrates with a size of 138*190*0.32 (mm) were subjected to surface ultrasonic cleaning;

[0113] S2: After ultrasonic cleaning of the surfaces of 16 copper sheets with a size of 134*184*2.00 (mm), the sheets were oxidized under the condition of 300 PPM oxygen content to form a copper oxide film on the surfaces of the copper sheets;

[0114] S3: stacking the processed ZTA ceramic substrate and the copper sheet with oxide film in sequence, placing them in a mold and pressing them tightly so that there is no obvious gap between the ZTA ceramic substrate and the copper sheet;

[0115] S4: Using the DBC process, the combination of the ZTA ceramic substrate and the copper sheet is placed in a nitrogen-protected tunnel furnace for sintering so that the copper sheet and the ZTA ceramic substrate are tightly combined to form an MCMI motherboard (the sintering conditions are: the highest temperature is 1080°C; the holding time is 30 minutes; the oxygen content in the sintering environment furnace is about 100PPM);

[0116] S5: Cut the MCMI master plate horizontally into 138*36.8*5.00 (mm) MCMI sheets by grinding wheel cutting;

[0117] S6: grinding and polishing the MCMI slice;

[0118] S7: Using the DBC process, a layer of 138*36.8*0.30 (mm) copper sheet is sintered on the upper and lower surfaces of the ground and polished MCMI sheet;

[0119] S8: The single-sided Al2O3-DBC is sintered on the MCMI substrate using the DBC process to form an integrated structure of a heat sink and a substrate as shown in FIG. 7(b), that is, the first packaging structure.

[0120] Assuming that the first packaging structure is based on an AlN-MCMI substrate, i.e., an AlN-type MCMI substrate, a specific implementation is as follows:

[0121] S1: Two AlN ceramic substrates with a size of 138*190*0.38 (mm) were ultrasonically cleaned on the surface, and then the AlN ceramic substrates were oxidized under an atmospheric condition of 1300° C. to form a layer of aluminum oxide film on the surface of the AlN ceramic substrates;

[0122] S2: After ultrasonic cleaning of the surfaces of three copper sheets with a size of 134*184*2.00 (mm), the sheets were oxidized under the condition of 300 PPM oxygen content to form a copper oxide film on the surfaces of the copper sheets;

[0123] S3: stacking the processed AlN ceramic substrate and the copper sheet with the oxide film in sequence, placing them in a mold and pressing them tightly so that there is no obvious gap between the AlN ceramic substrate and the copper sheet;

[0124] S4: Using the DBC process, the combination of the AlN ceramic substrate and the copper sheet is placed in a nitrogen-protected tunnel furnace for sintering so that the copper sheet and the AlN ceramic substrate are tightly combined to form an MCMI master (the sintering conditions are: the highest temperature is 1075°C; the holding time is 20 minutes; the oxygen content in the sintering environment furnace is about 60PPM);

[0125] S5: Using laser cutting to cut the MCMI master into 138*6.8*4.00 (mm) MCMI sheets horizontally;

[0126] S6: grinding and polishing the MCMI slice;

[0127] S7: using the DBC process to sinter a layer of copper sheet on the lower surface of the ground and polished MCMI sheet;

[0128] S8: sintering AIN-DBC on the MCMI substrate using the DBC process to form an integrated structure of heat sink and substrate as shown in FIG. 7( c ), namely the first packaging structure.

[0129] The above embodiments should not limit the present invention in any way, and any technical solutions obtained by equivalent replacement or equivalent conversion shall fall within the protection scope of the present invention.

Claims

1. A method for integrating metal and ceramic substrates, characterized in that: The specific steps include: Surface treating the ceramic substrate raw material and cutting it into initial ceramic substrates according to a preset first specification; Surface treating the metal sheet raw material and cutting it into initial metal sheets according to a preset second specification; Stacking and pressing a plurality of the initial ceramic substrates and the initial metal sheets in an alternating manner to obtain a combination of the ceramic substrates and the metal sheets; Sintering the assembly to form a MCMI motherboard; Cutting the MCMI motherboard according to a preset third specification to obtain a first MCMI sheet having the same number of layers as that of the MCMI motherboard; Grinding and polishing the first MCMI sheet to obtain a pretreated MCMI sheet; The pre-treated MCMI sheet is subjected to surface metallization treatment to obtain a MCMI substrate.

2. The integrated method according to claim 1, characterized in that: When the ceramic substrate raw material is surface treated, a ceramic substrate surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

3. The integrated method according to claim 1, characterized in that: When the metal sheet raw material is surface treated, the metal sheet surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

4. A substrate structure, characterized in that: The invention is manufactured by the integrated method as claimed in any one of claims 1 to 3.

5. A packaging structure, characterized in that: The packaging is obtained based on the substrate structure as claimed in claim 4.

6. A method for integrating a metal and a ceramic substrate, characterized in that: The specific steps include: Surface treating the ceramic substrate raw material and cutting it into initial ceramic substrates according to a preset first specification; Surface treating the metal sheet raw material and cutting it into initial metal sheets according to a preset second specification; Stacking and pressing a plurality of the initial ceramic substrates and the initial metal sheets in an alternating manner to obtain a combination of the ceramic substrates and the metal sheets; Sintering the assembly to form a MCMI motherboard; Cutting the MCMI motherboard according to a preset third specification to obtain a first MCMI sheet having the same number of layers as that of the MCMI motherboard; Combining and sintering at least two of the first MCMI sheets together to obtain a second MCMI sheet; Grinding and polishing the second MCMI sheet to obtain a pretreated MCMI sheet; The pre-treated MCMI sheet is subjected to surface metallization treatment to obtain a MCMI substrate.

7. The integrated method according to claim 6, characterized in that: When the ceramic substrate raw material is surface treated, a ceramic substrate surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

8. The integrated method according to claim 6, characterized in that: When the metal sheet raw material is surface treated, the metal sheet surface treatment method is selected according to the process required for sintering the assembly and the specific material of the ceramic substrate raw material.

9. A substrate structure, characterized in that: The method is manufactured by the integrated method as described in any one of claims 6 to 8.

10. A packaging structure, characterized in that: The packaging is obtained based on the substrate structure as claimed in claim 9.

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