CN118231263B - Method for preparing substrate, method for preparing power module, and power module - Google Patents
Method for preparing substrate, method for preparing power module, and power module Download PDFInfo
- Publication number
- CN118231263B CN118231263B CN202410218256.3A CN202410218256A CN118231263B CN 118231263 B CN118231263 B CN 118231263B CN 202410218256 A CN202410218256 A CN 202410218256A CN 118231263 B CN118231263 B CN 118231263B
- Authority
- CN
- China
- Prior art keywords
- substrate
- ceramic substrate
- conductive
- mounting hole
- mixed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000000758 substrate Substances 0.000 title claims abstract description 175
- 238000000034 method Methods 0.000 title claims description 30
- 239000000919 ceramic Substances 0.000 claims abstract description 97
- 238000005219 brazing Methods 0.000 claims abstract description 48
- 238000004519 manufacturing process Methods 0.000 claims abstract description 32
- 238000002360 preparation method Methods 0.000 claims abstract description 15
- 238000012545 processing Methods 0.000 claims abstract description 14
- 238000005520 cutting process Methods 0.000 claims abstract description 9
- 239000004020 conductor Substances 0.000 claims abstract description 8
- 229910000679 solder Inorganic materials 0.000 claims description 67
- 238000007639 printing Methods 0.000 claims description 27
- BERDEBHAJNAUOM-UHFFFAOYSA-N copper(I) oxide Inorganic materials [Cu]O[Cu] BERDEBHAJNAUOM-UHFFFAOYSA-N 0.000 claims description 15
- KRFJLUBVMFXRPN-UHFFFAOYSA-N cuprous oxide Chemical compound [O-2].[Cu+].[Cu+] KRFJLUBVMFXRPN-UHFFFAOYSA-N 0.000 claims description 15
- 229940112669 cuprous oxide Drugs 0.000 claims description 15
- 239000011159 matrix material Substances 0.000 claims description 7
- 239000002245 particle Substances 0.000 claims description 6
- 238000003466 welding Methods 0.000 claims description 6
- 238000004140 cleaning Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 3
- 239000007788 liquid Substances 0.000 abstract description 20
- 238000005530 etching Methods 0.000 abstract description 11
- 239000000126 substance Substances 0.000 abstract description 7
- 238000005476 soldering Methods 0.000 description 13
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 11
- 229910052802 copper Inorganic materials 0.000 description 10
- 239000010949 copper Substances 0.000 description 10
- 230000017525 heat dissipation Effects 0.000 description 7
- 230000008569 process Effects 0.000 description 5
- 239000002699 waste material Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000005553 drilling Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 230000003749 cleanliness Effects 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 238000003698 laser cutting Methods 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000011889 copper foil Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000001465 metallisation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000005201 scrubbing Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/48—Manufacture or treatment of parts, e.g. containers, prior to assembly of the devices, using processes not provided for in a single one of the groups H01L21/18 - H01L21/326 or H10D48/04 - H10D48/07
- H01L21/4814—Conductive parts
- H01L21/4846—Leads on or in insulating or insulated substrates, e.g. metallisation
- H01L21/4853—Connection or disconnection of other leads to or from a metallisation, e.g. pins, wires, bumps
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/48—Manufacture or treatment of parts, e.g. containers, prior to assembly of the devices, using processes not provided for in a single one of the groups H01L21/18 - H01L21/326 or H10D48/04 - H10D48/07
- H01L21/4814—Conductive parts
- H01L21/4846—Leads on or in insulating or insulated substrates, e.g. metallisation
- H01L21/4867—Applying pastes or inks, e.g. screen printing
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
- H01L23/49811—Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
- H01L23/49838—Geometry or layout
- H01L23/49844—Geometry or layout for individual devices of subclass H10D
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
- H01L23/49861—Lead-frames fixed on or encapsulated in insulating substrates
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
- H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
- H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
- H01L23/49866—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers characterised by the materials
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Geometry (AREA)
- Manufacturing Of Printed Circuit Boards (AREA)
- Structure Of Printed Boards (AREA)
Abstract
The invention discloses a preparation method of a substrate, a preparation method of a power module and the power module, wherein the preparation method of the substrate comprises the steps of S1, cutting a conductor according to a conductive pattern by laser to obtain a conductive piece, processing a mounting hole on the conductive piece, S2, pre-fixing the conductive piece on a ceramic substrate through mixed brazing paste, enabling the shape of the mixed brazing paste to be matched with that of the conductive piece, enabling the cross-sectional area of the mixed brazing paste on a projection surface of the ceramic substrate in the thickness direction to be smaller than that of the conductive piece, enabling part of the mixed brazing paste to be located in the mounting hole, S3, integrally placing the conductive piece and the ceramic substrate in the step S2 in a vacuum brazing furnace to be heated to obtain a conductive substrate, S4, taking out the conductive substrate after the vacuum brazing furnace is cooled, and cutting the conductive substrate to obtain a plurality of substrates. According to the preparation method of the substrate, the requirement on processing equipment is reduced, so that the production cost is reduced, chemical liquids such as etching liquid and the like are not needed, the pollution to the environment is reduced, and the production efficiency of the substrate is improved.
Description
Technical Field
The invention relates to the technical field of power modules, in particular to a preparation method of a substrate, a preparation method of a power module and the power module.
Background
In the field of power semiconductor modules, DBC (Direct Bond Copper, ceramic copper-clad plate) is generally used as a carrier of an IGBT chip in order to increase the heat dissipation, current carrying, and other capabilities of the device. The method for manufacturing the DBC by using the Al 2O3 ceramic is mainly a direct copper coating method, namely, copper is coated on two sides of the Al 2O3 ceramic, in the metallization process, the copper foil and the Al 2O3 ceramic can be directly connected without adding other substances, and then the copper is etched into corresponding conductive patterns according to circuit design or product structure.
However, in the conventional copper plating method, the manufacturer is often required to introduce a related etching production line, which increases the equipment cost, and the etching is required to use a chemical liquid such as a corresponding etching liquid, and the improper treatment of the chemical liquid can pollute the environment. In addition, the thick copper covered by the Al 2O3 ceramic has slower etching efficiency and lower precision, and the etching can etch away the copper except the conductive pattern, so that the material waste is caused.
Disclosure of Invention
The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, an object of the present invention is to provide a method for manufacturing a substrate, which reduces the requirements for processing equipment, thereby reducing the production cost, eliminating the need for chemical liquids such as etching solutions, reducing environmental pollution, and improving the production efficiency of the substrate.
Another object of the present invention is to provide a method for manufacturing a power module including the above method for manufacturing a substrate.
The invention also aims at providing a power module prepared by adopting the preparation method of the power module.
The preparation method of the substrate according to the embodiment of the first aspect of the invention comprises the following steps:
s1, cutting a conductor according to a conductive pattern by laser to obtain a conductive piece, and processing a mounting hole on the conductive piece;
S2, the conductive piece is pre-fixed on a ceramic substrate through mixed brazing paste, the shape of the mixed brazing paste is matched with that of the conductive piece, wherein the cross section area of the mixed brazing paste on a projection surface of the ceramic substrate in the thickness direction is smaller than that of the conductive piece, and part of the mixed brazing paste is positioned in the mounting hole;
S3, integrally placing the conductive piece and the ceramic substrate in the step S2 in a vacuum brazing furnace for heating to obtain a conductive substrate;
and S4, taking out the conductive matrix after the vacuum brazing furnace is cooled, and cutting the conductive matrix to obtain a plurality of substrates.
According to the method for manufacturing the substrate provided by the embodiment of the invention, through the steps S1-S4, the directly cut conductive piece can be soldered on the ceramic substrate, so that the substrate is obtained. Compared with the traditional etching method, the method reduces the requirement on processing equipment, thereby reducing the production cost, avoiding chemical liquids such as etching liquid and the like, reducing the pollution to the environment and improving the production efficiency of the substrate.
According to some embodiments of the invention, step S1 specifically comprises:
s21, printing the mixed brazing paste on the ceramic substrate through a printing screen;
s22, the conductive piece is pre-fixed on the ceramic substrate and then integrally placed in the tool.
According to some embodiments of the invention, a minimum distance between an edge of the mixed solder paste and an edge of the conductive member is L 1 on a projection surface of the ceramic substrate in a thickness direction, wherein L 1 is 0.2mm or less and L 1 is or less and 0.3mm, and the mixed solder paste covers a bottom of the mounting hole on the projection surface of the ceramic substrate in the thickness direction.
According to some embodiments of the invention, a minimum distance between an edge of the opening of the printing screen and an edge of the conductive member is L 2 on a projection surface of the ceramic substrate in a thickness direction, wherein L 2 is 0.2mm or less and L 2 is or less than 0.3mm, and the opening of the printing screen covers a bottom of the mounting hole on the projection surface of the ceramic substrate in the thickness direction.
According to some embodiments of the invention, the thickness of the printing screen in the thickness direction of the ceramic substrate is D, wherein D is 0.1 mm.ltoreq.D.ltoreq.0.2 mm.
According to some embodiments of the invention, step S1 is preceded by
S0, processing a positioning hole on the ceramic substrate, and cleaning the ceramic substrate;
wherein, in step S22, the fixture is installed through the positioning hole.
According to some embodiments of the invention, before step S1, further comprises:
S20, removing the oxide of the conductor.
According to some embodiments of the invention, the mixed brazing paste comprises CuSnTi brazing paste and cuprous oxide, wherein the mass ratio of the cuprous oxide to the brazing paste is alpha, and alpha is 1% -2%.
According to some embodiments of the invention, the cuprous oxide has a particle size d, wherein d satisfies 45 μm.ltoreq.d.ltoreq.65 μm.
According to some embodiments of the invention, the brazing temperature is T and the brazing duration is T in the step S3, wherein T, T is 900 ℃ and less than or equal to T and less than or equal to 950 ℃ and 20min and less than or equal to T and less than or equal to 30min respectively.
The preparation method of the power module according to the embodiment of the second aspect of the invention comprises the following steps:
S1', the connecting parts of the power pins of the frame are pre-fixed in the mounting holes of the substrate through solder paste, and the substrate is prepared by adopting the preparation method of the substrate in the embodiment of the first aspect of the invention;
s2', welding the substrate and the frame.
According to some embodiments of the invention, in step S1', the solder paste is placed in the mounting hole by printing or spray printing, and at least part of the connecting portion is located in the mounting hole.
According to some embodiments of the invention, a cross-sectional area of the mounting hole is larger than a cross-sectional area of the connection portion on a projection plane of the substrate in a thickness direction.
According to some embodiments of the invention, the minimum distance between the edge of the mounting hole and the edge of the connecting portion is L 3 in the length direction of the substrate, wherein L 3 is 0.05 mm.ltoreq.L 3.ltoreq.0.1 mm, and/or the minimum distance between the edge of the mounting hole and the edge of the connecting portion is L 4 in the width direction of the substrate, wherein L 4 is 0.05 mm.ltoreq.L 4.ltoreq.0.1 mm.
According to the power module of the embodiment of the third aspect of the invention, the power module is prepared by adopting the preparation method of the power module of the embodiment of the second aspect of the invention.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:
Fig. 1 is a flowchart of a method of manufacturing a substrate according to an embodiment of the present invention;
FIG. 2 is a flow chart of a conductive element of a substrate according to an embodiment of the invention;
FIG. 3 is a schematic view of a substrate and frame of a power module according to an embodiment of the invention;
FIG. 4 is an enlarged view of a portion of a substrate and frame of the power module shown in FIG. 3;
Fig. 5 is a side view of a substrate and frame of a power module according to an embodiment of the invention;
fig. 6 is an enlarged view of a portion of a substrate and frame of the power module of fig. 5.
Reference numerals:
100, a power module:
10 parts of conductors, 11 parts of conductive patterns, 12 parts of conductive pieces, 13 parts of mounting holes, 20 parts of mixed solder paste, 30 parts of ceramic substrates, 31 parts of positioning holes, 40 parts of conductive substrates, 50 parts of substrates, 60 parts of frames, 61 parts of power pins, 62 parts of connecting parts and 70 parts of solder paste;
200, a tool.
Detailed Description
A method of manufacturing the substrate 50 according to an embodiment of the first aspect of the present invention is described below with reference to fig. 1 to 2.
As shown in fig. 1 and 2, a method for preparing a substrate 50 according to an embodiment of the first aspect of the present invention includes the steps of:
s1, cutting the conductor 10 according to the conductive pattern 11 by laser to obtain a conductive piece 12, and processing a mounting hole 13 on the conductive piece 12. That is, the unnecessary portion on the conductive member 12 is removed by laser cutting in accordance with the conductive pattern 11 to process the conductive body 10 into the conductive member 12. Wherein the electrical conductor 10 may be a copper sheet having a thickness of 0.2 mm. The conductive member 12 may be used for mounting a power chip or for dissipating heat from the power module 100.
Wherein, can process out mounting hole 13 through laser cutting on electrically conductive piece 12, when pin and electrically conductive piece 12 are assembled, the one end of pin can cooperate in mounting hole 13 to make the pin be limited by mounting hole 13, avoid the pin to remove by a wide margin, mounting hole 13 plays better locate action this moment, has guaranteed the stability of the relative position of electrically conductive piece 12 and power pin.
S2, the conductive piece 12 is pre-fixed on the ceramic substrate 30 through the mixed brazing paste 20, and the shape of the mixed brazing paste 20 is matched with the shape of the conductive piece 12, so that the conductive piece 12 is firmly pre-fixed on the ceramic substrate 30, and leakage of the mixed brazing paste 20 is avoided.
Wherein the cross-sectional area of the mixed solder paste 20 on the projection surface in the thickness direction (e.g., the front-rear direction in fig. 4) of the ceramic substrate 30 is smaller than the cross-sectional area of the conductive member 12. Since the mixed solder paste 20 is melted at a high temperature in the vacuum brazing furnace, the area of the mixed solder paste 20 is set smaller, and the liquid mixed solder paste 20 is prevented from flowing to the outside of the conductive member 12 during the brazing process while the conductive member 12 is firmly brazed on the ceramic substrate 30, thereby reducing the waste of the mixed solder paste 20 and ensuring the regularity of the surface of the substrate 50.
Part of the mixed solder paste 20 is located in the mounting hole 13, and at this time, the mounting hole 13 may be adapted to mount the pin of the power module 100, that is, the pin may be connected with the ceramic substrate 30 through the mixed solder paste 20 in the mounting hole 13, so as to achieve a fixed connection between the pin and the substrate 50, and the pin may be electrically connected with the conductive member 12 through the mixed solder paste 20.
Alternatively, the ceramic substrate 30 may be an Al 2O3 ceramic substrate 30. But is not limited thereto.
And S3, integrally placing the conductive piece 12 and the ceramic substrate 30 in the step S2 in a vacuum brazing furnace for heating to obtain the conductive matrix 40. By this step, the conductive member 12 can be firmly soldered to the ceramic substrate 30, and the conductive member 12 is prevented from falling off during the processing of the power module 100.
And S4, taking out the conductive matrix 40 after the vacuum brazing furnace is cooled, and cutting the conductive matrix 40 to obtain a plurality of substrates 50. That is, a plurality of substrates 50 can be integrated together for processing, improving the production efficiency of the substrates 50.
According to the method for manufacturing the substrate 50 of the embodiment of the present invention, the directly cut conductive member 12 may be soldered to the ceramic substrate 50 through the above steps S1 to S4 to obtain the substrate 50. Compared with the traditional etching method, the method reduces the requirement on processing equipment, thereby reducing the production cost, avoiding chemical liquids such as etching liquid and the like, reducing the pollution to the environment and improving the production efficiency of the substrate 50.
According to some embodiments of the invention, step S2 specifically comprises:
And S21, printing the mixed brazing paste 20 on the ceramic substrate 30 through a printing screen. Wherein the mesh of the printing screen is positioned at the same location as the conductive member 12 on the ceramic substrate 30 such that only the area of the ceramic substrate 30 where the conductive member 12 is disposed is provided with the mixed solder paste 20, while other areas of the ceramic substrate 30 are free of the mixed solder paste 20. Thus, waste of the mixed solder paste 20 can be reduced, the cost can be reduced, and the power module 100 can work normally.
S22, the conductive piece 12 is pre-fixed on the ceramic substrate 30 and then integrally placed in the tool 200. The movement of the ceramic substrate 30 and the conductive piece 12 can be limited by the fixture 200, so that the ceramic substrate 30 and the conductive piece 12 are moved to a vacuum brazing furnace, the relative change of the positions of the conductive piece 12 and the ceramic substrate 30 is avoided, and the yield of the substrate 50 can be improved.
Further, on the projection surface in the thickness direction of the ceramic substrate 30, the minimum distance between the edge of the mixed solder paste 20 and the edge of the conductive member 12 is L 1, wherein L 1 satisfies that 0.2 mm.ltoreq.L 1.ltoreq.0.3 mm. When L 1 <0.2mm, the minimum distance between the edge of the mixed solder paste 20 and the edge of the conductive member 12 is small, i.e., the edge of the mixed solder paste 20 on the ceramic substrate 30 is approximately flush with the edge of the conductive member 12, resulting in the liquid mixed solder paste 20 flowing to the outside of the conductive member 12 during soldering, and when L 1 >0.3mm, the minimum distance between the edge of the mixed solder paste 20 and the edge of the conductive member 12 is large, the size of the mixed solder paste 20 is small, and the connection reliability of the conductive member 12 and the ceramic substrate 30 is lowered. Thus, by making L 1 satisfy 0.2 mm.ltoreq.L 1.ltoreq.0.3 mm, the liquid mixed solder paste 20 can be prevented from flowing to the outside of the conductive member 12 during soldering while ensuring the connection reliability of the conductive member 12 and the ceramic substrate 30.
Referring to fig. 5 and 6, the mixed solder paste 20 covers the bottom of the mounting hole 13 on the projection surface of the ceramic substrate 30 in the thickness direction. That is, a part of the mixed solder paste 20 on the ceramic substrate 30 is located on the conductive member 12 and the ceramic substrate 30, the part of the mixed solder paste 20 is used to solder the conductive member 12 to the ceramic substrate 30, and another part of the mixed solder paste 20 covers the entire bottom of the mounting hole 13 for firmly soldering the pins to the ceramic substrate 30 to achieve reliable connection of the substrate 50 to the pins.
According to some embodiments of the present invention, the minimum distance between the edge of the openings of the printing screen and the edge of the conductive member 12 on the projected surface of the ceramic substrate 30 in the thickness direction is L 2, wherein L 2 satisfies that 0.2 mm.ltoreq.L 2.ltoreq.0.3 mm. When L 2 <0.2mm, the minimum distance between the open edge of the printing screen and the edge of the conductive member 12 is small, and since the mixed solder paste 20 is printed on the ceramic substrate 30 through the printing screen, that is, the edge of the mixed solder paste 20 on the ceramic substrate 30 is substantially flush with the edge of the conductive member 12, resulting in the liquid mixed solder paste 20 flowing to the outside of the conductive member 12 during soldering, when L 2 >0.3mm, the minimum distance between the open edge of the printing screen and the edge of the conductive member 12 is large, and the size of the mixed solder paste 20 is small, the connection reliability of the conductive member 12 and the ceramic substrate 30 is lowered. Thus, by making L 1 satisfy 0.2 mm.ltoreq.L 2.ltoreq.0.3 mm, the liquid mixed solder paste 20 can be prevented from flowing to the outside of the conductive member 12 during soldering while ensuring the connection reliability of the conductive member 12 and the ceramic substrate 30.
On the projection surface of the ceramic substrate 30 in the thickness direction, the openings of the printing screen cover the bottoms of the mounting holes 13, that is, the mixed solder paste 20 printed on the ceramic substrate 30 by the printing screen can cover the bottoms of the mounting holes 13, so that the mounting holes 13 are ensured to have enough mixed solder paste 20, the pins are firmly fixed in the mounting holes 13, and the reliability of the electrical connection between the pins and the conductive members 12 is ensured.
According to some embodiments of the present invention, the thickness of the printing screen in the thickness direction of the ceramic substrate 30 (e.g., the front-to-back direction of FIG. 4) is D, where D satisfies 0.1 mm.ltoreq.D.ltoreq.0.2 mm. That is, the thickness of the mixed solder paste 20 in the thickness direction of the ceramic substrate 30 is 0.1mm to 0.2mm. By the arrangement, the melted mixed brazing paste 20 can be filled in the gap between the conductive piece 12 and the ceramic substrate 30, so that the conductive piece 12 is firmly connected to the ceramic substrate 30, the mixed brazing paste 20 is prevented from flowing to the outside of the conductive piece 12, and the waste of the mixed brazing paste 20 is further reduced.
According to some embodiments of the invention, step S1 is preceded by
S0, processing a positioning hole 31 on the ceramic substrate 30, and cleaning the ceramic substrate 30;
wherein, in step S22, the tooling 200 is installed through the positioning hole 31.
As shown in fig. 2, the ceramic substrate 30 is processed with a plurality of positioning holes 31, the plurality of positioning holes 31 being located at the middle of the ceramic substrate 30, and the remaining positioning holes 31 being uniformly spaced apart in the circumferential direction of the ceramic substrate 30. In the description of the present invention, "plurality" means two or more. By arranging the positioning holes 31 on the ceramic substrate 30, on one hand, the positioning holes 31 can realize the positioning of the printing screen and the ceramic substrate 30 so as to ensure that the mixed solder paste 20 can be accurately printed on the ceramic substrate 30 at the position where the conductive piece 12 is placed, and on the other hand, the positioning holes 31 can realize the positioning of the fixture 200 and the ceramic substrate 30 so as to ensure that the ceramic substrate 30 and the conductive piece 12 can be accurately installed in the fixture 200, thereby improving the production efficiency of the substrate 50.
Optionally, after the positioning holes 31 are machined, the surface of the ceramic substrate 30 needs to be cleaned, so as to ensure the cleanliness of the surface of the ceramic substrate 30.
In some alternative embodiments, step S21 further comprises, prior to:
S20, removing oxide of the conductive element 12. For example, the oxide on the surface of the conductive member 10 may be removed by scrubbing with alcohol, and then the conductive member 10 is cut according to the conductive pattern 11, and the cut conductive member is cleaned again, so that the surface of the conductive member 12 is free of oxide and cutting scraps, the cleanliness of the conductive member 12 is ensured, the conductive member 12 can be more stably arranged on the ceramic substrate 30, and the power chip is conveniently arranged on the conductive member 12, thereby reducing the energy consumption of the power module 100.
According to some embodiments of the invention, the mixed solder paste 20 comprises CuSnTi solder paste and cuprous oxide, wherein the mass ratio of the cuprous oxide is alpha, and alpha is 1-2%. When alpha is less than 1%, the content of cuprous oxide is less, and the cuprous oxide cannot be uniformly distributed in CuSnTi solder paste, so that the mixing uniformity of the mixed solder paste 20 is poor, the height of the mixed solder paste 20 is inconsistent (namely, the welding seam is inconsistent), the flatness of the substrate 50 is seriously affected during brazing, and when alpha is more than 2%, the content of the cuprous oxide is more, so that the content of CuSnTi solder paste is less, the weldability of the mixed solder paste 20 is reduced, and the connection reliability of the conductive piece 12 and the ceramic substrate 30 is reduced. Thus, by making a 1% or less and 2% or less satisfied, the connection reliability of the conductive member 12 and the ceramic substrate 30 can be improved while ensuring the flatness of the substrate 50, and separation of the conductive member 12 from the ceramic substrate 30 can be avoided.
Further, the particle size of the cuprous oxide is d, wherein d is 45 μm or less and d is 65 μm or less. When d <45 mu m, the particle size of the cuprous oxide is smaller, the liquid mixed solder paste 20 overflows more during soldering, namely, the part of the liquid mixed solder paste 20 overflows the conductive piece 12 is more, the capillary filling force of the mixed solder paste 20 is larger, the welding holes are smaller, and the weldability of the mixed solder paste 20 is affected, when d >65 mu m, the particle size of the cuprous oxide is larger, and although the liquid mixed solder paste 20 overflows less during soldering, the capillary filling force of the mixed solder paste 20 is smaller, the welding holes are larger, and the weldability of the mixed solder paste 20 is affected. Thus, by making the particle diameter d of cuprous oxide satisfy 45 μm.ltoreq.d65 μm.ltoreq.dL, the overflow of the liquid mixed solder paste 20 during brazing can be effectively avoided, and the solderability of the mixed solder paste 20 is ensured, thereby ensuring the connection reliability of the conductive member 12 and the ceramic substrate 30.
According to some embodiments of the invention, the brazing temperature is T and the brazing duration is T in the step S3, wherein T, T is respectively 900 ℃ and less than or equal to T and less than or equal to 950 ℃ and 20min and less than or equal to T and less than or equal to 30min. So set up, when guaranteeing that mixed drilling paste 20 can melt, avoid mixing drilling paste 20 excessively to melt and influence the performance of mixing drilling paste 20.
Alternatively, in step S3, the vacuum degree of the vacuum brazing furnace may be controlled to be 10 -2 levels.
In some alternative embodiments, the substrate 50 may be a ceramic copper clad laminate. For example, a pad (i.e., the conductive member 12) is disposed on one side of the ceramic substrate 30 in the thickness direction, and a power chip may be disposed on the pad, or the pad (i.e., the conductive member 12) and the heat dissipation layer are disposed on two sides of the ceramic substrate 30 in the thickness direction, and the surface of the heat dissipation layer on one side far from the pad may be flush with the bottom surface of the plastic package body and exposed outside the plastic package body. When the power chip works to generate heat, the heat can be transferred to the heat dissipation layer through the bonding pad and the ceramic substrate 30, and the heat dissipation layer exchanges heat with the outside to realize heat dissipation of the intelligent power module. For example, the materials of the bonding pad, the ceramic substrate 30 and the heat dissipation layer may be respectively configured as a copper layer, a ceramic layer and a copper layer, so as to facilitate the normal use of the substrate 50.
As shown in fig. 2 to 5, a method for manufacturing a power module 100 according to an embodiment of the second aspect of the present invention includes the steps of:
S1', the connection portions 62 of the power pins 61 of the frame 60 are pre-fixed in the mounting holes 13 of the substrate 50 by solder paste 70, and the substrate 50 is manufactured by the manufacturing method of the substrate 50 according to the embodiment of the first aspect of the present invention. The solder paste 70 may be a Sn-based solder. But is not limited thereto.
S2', the substrate 50 and the frame 60 are welded. For example, the power pins 61 may be securely fixed in the mounting holes 13 by reflow soldering. In order to ensure that the conductive member 12 is not separated from the ceramic substrate 30 during reflow soldering, the temperature of the solder paste 70 during reflow soldering needs to be less than the soldering temperature T, and the power pin 61 is electrically connected with the substrate 50, so that the conductive member 12 and the ceramic substrate 30 are prevented from being relatively displaced, and the power module 100 is more reliable. Wherein the power pins 61 are electrically connected to the conductive member 12 through the solder paste 70 and the mixed solder paste 20.
According to the method for manufacturing the power module 100 of the embodiment of the invention, the power pins 61 are limited to the mounting holes 13 in the welding process through the steps S1 '-S2', so that the power pins 61 are prevented from moving greatly, the mounting holes 13 play a good role in positioning, the relative movement between the power pins 61 and the substrate 50 is prevented when the power pins 61 are welded, the stability of the relative positions of the substrate 50 and the power pins 61 is ensured, the efficiency of one-step molding when the substrate 50 and the power pins 61 are welded is improved, and the rejection risk of the power module 100 is reduced.
According to some embodiments of the present invention, in step S1', the solder paste 70 is placed in the mounting hole 13 by printing or spray printing, which increases the diversity of placing the solder paste 70 in the mounting hole 13 and improves the production efficiency of the power module 100. At least a portion of the connecting portion 62 is located within the mounting hole 13. For example, a part of the connection portion 62 may be placed in the mounting hole 13 when the power pin 61 is pre-fixed, or the connection portion 62 may be entirely placed in the mounting hole 13 when the power pin 61 is pre-fixed. This allows the mounting hole 13 to effectively restrict the movement of the connection portion 62, and ensures the stability of the position of the power pin 61.
According to some embodiments of the present invention, the cross-sectional area of the mounting hole 13 is larger than the cross-sectional area of the connection portion 62 on a projection plane of the thickness direction (e.g., the front-rear direction of fig. 4) of the substrate 50. So set up, the connecting portion 62 of being convenient for is placed in mounting hole 13, makes simultaneously and has the clearance between connecting portion 62 and the mounting hole 13, and the solder paste after melting can fill between mounting hole 13 and connecting portion 62 when doing benefit to the reflow soldering, avoids liquid mixed solder paste 20 to flow to connecting portion 62.
Further, as shown in FIGS. 3 and 4, the minimum distance between the edge of the mounting hole 13 and the edge of the connecting portion 62 in the longitudinal direction (e.g., the left-right direction in FIG. 3) of the substrate 50 is L 3, where L 3 satisfies 0.05 mm.ltoreq.L 3.ltoreq.0.1 mm. When L 3 <0.05mm, the minimum distance between the edge of the mounting hole 13 and the edge of the connecting portion 62 is small, when the processing error between the mounting hole 13 and the connecting portion 62 increases, the connecting portion 62 cannot be placed in the mounting hole 13, and the relative movement between the power pin 61 and the substrate 50 is easy to occur, when L 3 >0.1mm, the minimum distance between the edge of the mounting hole 13 and the edge of the connecting portion 62 is large, the size of the mounting hole 13 is large, and the melted solder paste 70 may not fill the mounting hole 13 during reflow soldering, so that the surface of the substrate 50 is concave. Thus, by making L 3 satisfy 0.05 mm.ltoreq.L 3.ltoreq.0.1 mm, the flatness of the surface of the substrate 50 can be improved while ensuring stable relative positions of the power pins 61 and the substrate 50.
Similarly, as shown in FIGS. 5 and 6, the minimum distance between the edge of the mounting hole 13 and the edge of the connecting portion 62 in the width direction (e.g., the up-down direction in FIG. 3) of the substrate 50 is L 4, where L 4 satisfies 0.05 mm.ltoreq.L 4.ltoreq.0.1 mm. By doing so, the flatness of the surface of the substrate 50 can be improved while also ensuring stable relative positions of the power pins 61 and the substrate 50.
Alternatively, the minimum distance between the connection portion 62 and the bottom wall of the mounting hole 13 may be between 0.1mm and 0.2mm in the thickness direction of the substrate 50.
According to the power module 100 of the embodiment of the third aspect of the present invention, the power module 100 is manufactured by using the manufacturing method of the power module 100 of the embodiment of the second aspect of the present invention.
According to the power module 100 of the third aspect of the present invention, by adopting the method for manufacturing the power module 100, the production efficiency of the power module 100 can be improved, and the yield of the power module 100 can be improved.
Other configurations and operations of the power module 100 according to embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail herein.
In the description of the present invention, it should be understood that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
In the description of the present application, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.
In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.
Claims (14)
1. A method for manufacturing a substrate, comprising the steps of:
s1, cutting a conductor according to a conductive pattern by laser to obtain a conductive piece, and processing a mounting hole on the conductive piece;
S2, the conductive piece is pre-fixed on a ceramic substrate through mixed brazing paste, the shape of the mixed brazing paste is matched with that of the conductive piece, wherein the cross section area of the mixed brazing paste on a projection surface of the ceramic substrate in the thickness direction is smaller than that of the conductive piece, and part of the mixed brazing paste is positioned in the mounting hole;
S3, integrally placing the conductive piece and the ceramic substrate in the step S2 in a vacuum brazing furnace for heating to obtain a conductive substrate;
S4, taking out the conductive matrix after the vacuum brazing furnace is cooled, and cutting the conductive matrix to obtain a plurality of substrates;
Wherein, on a projection surface of the ceramic substrate in the thickness direction, the minimum distance between the edge of the mixed brazing paste and the edge of the conductive piece is L 1, wherein, L 1 satisfies that L 1 which is more than or equal to 0.2mm and less than or equal to 0.3mm;
And the mixed brazing paste covers the bottom of the mounting hole on the projection surface of the ceramic substrate in the thickness direction.
2. The method of manufacturing a substrate according to claim 1, wherein step S2 specifically comprises:
s21, printing the mixed brazing paste on the ceramic substrate through a printing screen;
s22, the conductive piece is pre-fixed on the ceramic substrate and then integrally placed in the tool.
3. The method according to claim 2, wherein a minimum distance between an opening edge of the printing screen and an edge of the conductive member on a projection surface in a thickness direction of the ceramic substrate is L 2, wherein L 2 satisfies 0.2 mm.ltoreq.L 2.ltoreq.0.3 mm;
And on the projection surface of the ceramic substrate in the thickness direction, the bottom of the mounting hole is covered by the opening of the printing screen.
4. The method of producing a substrate according to claim 3, wherein the thickness of the printing screen in the thickness direction of the ceramic substrate is D, wherein D satisfies 0.1 mm.ltoreq.D.ltoreq.0.2 mm.
5. The method of claim 2, further comprising, before step S1
S0, processing a positioning hole on the ceramic substrate, and cleaning the ceramic substrate;
wherein, in step S22, the fixture is installed through the positioning hole.
6. The method of manufacturing a substrate according to claim 2, further comprising, before step S1:
S20, removing the oxide of the conductor.
7. The method for preparing the substrate according to any one of claims 1 to 6, wherein the mixed brazing paste comprises CuSnTi brazing paste and cuprous oxide, wherein the mass ratio of the cuprous oxide is alpha, and alpha is 1% -2%.
8. The method for producing a substrate according to claim 7, wherein the cuprous oxide has a particle diameter d, and wherein d satisfies 45 μm.ltoreq.d.ltoreq.65 μm.
9. The method according to any one of claims 1 to 6, wherein the brazing temperature is T and the brazing time period is T in the step S3, wherein the T, T satisfies that T is 900 ℃ and 950 ℃ and T is 20min and T is 30min, respectively.
10. The preparation method of the power module is characterized by comprising the following steps of:
s1', connecting parts of power pins of a frame are pre-fixed in mounting holes of a substrate through solder paste, and the substrate is prepared by adopting the preparation method of the substrate according to any one of claims 1-9;
s2', welding the substrate and the frame.
11. The method according to claim 10, wherein in step S1', the solder paste is placed in the mounting hole by printing or spray printing, and at least part of the connecting portion is located in the mounting hole.
12. The method of manufacturing a power module according to claim 10, wherein a cross-sectional area of the mounting hole is larger than a cross-sectional area of the connection portion on a projection plane of the substrate in a thickness direction.
13. The method of manufacturing a power module according to claim 12, wherein a minimum distance between an edge of the mounting hole and an edge of the connection portion in a length direction of the substrate is L 3, wherein L 3 satisfies 0.05 mm.ltoreq.L 3.ltoreq.0.1 mm, and/or
The minimum distance between the edge of the mounting hole and the edge of the connecting portion in the width direction of the substrate is L 4, wherein L 4 is 0.05 mm-L 4 -0.1 mm.
14. A power module, characterized in that it is manufactured by a method according to any one of claims 10-13.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410218256.3A CN118231263B (en) | 2024-02-27 | 2024-02-27 | Method for preparing substrate, method for preparing power module, and power module |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410218256.3A CN118231263B (en) | 2024-02-27 | 2024-02-27 | Method for preparing substrate, method for preparing power module, and power module |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN118231263A CN118231263A (en) | 2024-06-21 |
| CN118231263B true CN118231263B (en) | 2025-02-11 |
Family
ID=91508084
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410218256.3A Active CN118231263B (en) | 2024-02-27 | 2024-02-27 | Method for preparing substrate, method for preparing power module, and power module |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118231263B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110012597A (en) * | 2019-04-12 | 2019-07-12 | 中国科学院电工研究所 | A kind of ceramic copper clad circuit board and preparation method thereof |
| CN114373685A (en) * | 2022-01-07 | 2022-04-19 | 井敏 | Active metal brazing ceramic substrate and manufacturing method thereof |
| CN117457504A (en) * | 2023-12-22 | 2024-01-26 | 成都万士达瓷业有限公司 | Production method for copper-clad ceramic packaging surface |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115958263A (en) * | 2022-12-27 | 2023-04-14 | 南通威斯派尔半导体技术有限公司 | Technological method for preventing solder from overflowing in brazing process of AMB substrate |
| CN220400582U (en) * | 2023-06-30 | 2024-01-26 | 海信家电集团股份有限公司 | Substrate of intelligent power module, intelligent power module and electronic equipment |
| CN117594461A (en) * | 2023-11-20 | 2024-02-23 | 珠海格力电器股份有限公司 | Intelligent power module packaging method and device |
-
2024
- 2024-02-27 CN CN202410218256.3A patent/CN118231263B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110012597A (en) * | 2019-04-12 | 2019-07-12 | 中国科学院电工研究所 | A kind of ceramic copper clad circuit board and preparation method thereof |
| CN114373685A (en) * | 2022-01-07 | 2022-04-19 | 井敏 | Active metal brazing ceramic substrate and manufacturing method thereof |
| CN117457504A (en) * | 2023-12-22 | 2024-01-26 | 成都万士达瓷业有限公司 | Production method for copper-clad ceramic packaging surface |
Also Published As
| Publication number | Publication date |
|---|---|
| CN118231263A (en) | 2024-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7948076B2 (en) | Semiconductor chip assembly with post/base heat spreader and vertical signal routing | |
| JP5691475B2 (en) | Semiconductor device and manufacturing method thereof | |
| CN109256337B (en) | Eutectic welding device and method for millimeter-scale elements with circumferences | |
| WO2017154289A1 (en) | Semiconductor device and semiconductor device manufacturing method | |
| US20030124829A1 (en) | Interconnection method entailing protuberances formed by melting metal over contact areas | |
| CN112771665B (en) | Packaging structure, electric vehicle and electronic device | |
| CN118231263B (en) | Method for preparing substrate, method for preparing power module, and power module | |
| CN118248663B (en) | Substrate for power module, conductive substrate and power module thereof | |
| CN118231372B (en) | Substrate for power module, conductive substrate and power module thereof | |
| CN116864404A (en) | Power device and preparation method thereof | |
| CN217387148U (en) | Substrate structure and substrate comprising same | |
| JP2004039988A (en) | Circuit board for element mounting and electronic device | |
| CN213692043U (en) | Intelligent power module | |
| JP6496622B2 (en) | Ceramic wiring board and electronic component storage package | |
| CN115206891A (en) | Semiconductor circuit for improving bonding force of substrate and sealing layer and manufacturing method thereof | |
| CN117355936A (en) | Semiconductor device with a semiconductor device having a plurality of semiconductor chips | |
| CN117157759A (en) | Semiconductor device | |
| CN222366418U (en) | A standard power device boss-shaped embedded package PCB board | |
| CN221805505U (en) | Semiconductor packaging structure | |
| CN221447154U (en) | Integrated circuit packaging structure and chip | |
| CN222749495U (en) | A thin and light integrated circuit frame and semiconductor device | |
| CN215898073U (en) | Three-dimensional circuit board of 3D | |
| CN221670113U (en) | Power device embedded packaging PCB structure | |
| CN221283412U (en) | High power density point power supply | |
| CN221947143U (en) | Power modules, inverters and mechatronics with heat sinks |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |