Single-sided copper-clad ceramic plate and packaging method thereof, and power module packaging structure

Abstract

The invention relates to a single-sided copper-clad ceramic plate, a packaging method thereof and a power module packaging structure, the single-sided copper-clad ceramic plate comprises an insulating heat-conducting ceramic substrate, a copper layer circuit board and a first plastic package body, and the insulating heat-conducting ceramic substrate and the copper layer circuit board are sintered into a whole through a low-temperature sintering material; and the first plastic package body wraps the side surfaces of the insulating heat-conducting ceramic substrate and the copper layer circuit board. According to the single-sided copper-clad ceramic plate, high-temperature welding is replaced by low-temperature sintering, so that overall deformation and warping caused by inconsistent thermal expansion are reduced, the process difficulty is greatly reduced, material bonding interfaces are few, defects such as welding cavities and welding layering generated by two times of high temperature are greatly reduced, meanwhile, the process number and used processing materials are also greatly reduced, and the production cost is reduced. And the processing technology is simpler, the manufacturing cost is lower, the method is more suitable for large-scale production, and the overall advantages are obvious. The low-temperature sintered material can rapidly conduct heat and dissipate heat, has better toughness, plays a buffering role, and reduces the risk of breakage and layering of the middle bonding layer.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and in particular to a single-sided copper-clad ceramic board and a packaging method thereof, and a power module packaging structure. Background Art

[0002] IGBT / MOSFET power modules are widely used in various energy fields, especially new energy vehicles. When the power module is running at high power and high current, the chip inside the power module will generate a lot of heat, which must be dissipated in time. Otherwise, the chip temperature will rise too high, resulting in unstable chip performance and even direct damage and failure of the chip.

[0003] In the prior art, high thermal conductivity double-sided copper-clad ceramic boards are generally used to connect chips. Double-sided copper-clad ceramic boards not only have stable and reliable circuit functions, but can also carry large currents, and have high heat dissipation performance and rapid heat conduction and heat dissipation. The main double-sided copper-clad ceramic boards currently used are DBC (Direct Bonding Copper) direct copper-clad ceramic boards and AMB (Active Metal Brazing) active metal welding ceramic boards.

[0004] The main structure of DBC or AMB consists of three parts: metal copper layer, ceramic dielectric layer and metal brazing material. The metal brazing material forms a sandwich structure between the middle insulation layer and the copper layers on both sides. Among them, the copper circuit layer welded to the chip has the functions of conducting electricity and heat dissipation at the same time, the middle ceramic layer plays the role of isolation insulation (insulation withstand voltage>2.5KV), heat conduction and mechanical support, and the copper layer exposed on the top is connected to the external heat dissipation module to play the role of rapid heat conduction and heat dissipation. This double-layer copper-clad structure can not only provide high-power and high-current circuits, but also quickly transfer and dissipate the heat generated when the chip is running, providing a reliable and stable operating temperature environment for the chip.

[0005] DBC technology is a composite substrate formed by directly bonding copper to the surface of AI2O3 or AIN ceramics through hot melt bonding at high temperature (1065℃), and then etching the corresponding pattern on the copper-clad surface according to the circuit design or product structure. AMB technology is a method of combining ceramics and metals by using active metal elements in solder (such as Ti / Ag / Zr / Cu). At high temperature (above 800℃), a reaction layer that can be wetted by liquid solder is formed on the surface of the ceramic, and the ceramic and copper layers are welded and bonded. Then, through two etchings, the sintered and bonded copper layer and solder layer are etched into the required circuits. Due to the difference in the thermal expansion coefficient CTE between copper and ceramics, the inconsistent thermal expansion during high-temperature sintering causes deformation and warping. The size and thickness of the ceramic and copper layers need to be controlled to a certain extent. At the same time, a sandwich structure with the same material on the top and bottom needs to be adopted to reduce the overall warping.

[0006] The bonding strength between the copper layer and ceramic of DBC and AMB depends entirely on the adhesion of the intermediate welding layer. Due to the difference in thermal expansion coefficients (CTE) between copper and ceramic, large residual stress is generated during the high-temperature sintering bonding process, which is not conducive to forming excellent bonding performance. During the long working hours and frequent high and low temperature conversions after chip packaging, the intermediate dielectric layer is prone to fracture and delamination, affecting product reliability and leading to product failure. Summary of the invention

[0007] The invention provides a single-sided copper-clad ceramic board and a packaging method thereof, and a power module packaging structure, which are used to solve the technical problems that the single-sided copper-clad ceramic board is easy to warp and the etching circuit process is complicated.

[0008] The technical solution provided by the present invention is: a single-sided copper-clad ceramic board, comprising an insulating thermally conductive ceramic substrate, a copper layer circuit board and a first plastic packaging body, wherein the insulating thermally conductive ceramic substrate and the copper layer circuit board are sintered into one body by a low-temperature sintering material, and the first plastic packaging body wraps the sides of the insulating thermally conductive ceramic substrate and the copper layer circuit board.

[0009] Wherein, the copper layer circuit board is also provided with a boss or a groove.

[0010] Wherein, the low-temperature sintering material is sintered silver, sintered copper, solder paste, prefabricated tin sheet or non-conductive heat dissipation glue.

[0011] Wherein, the layer thickness of the low-temperature sintering material is 30-80 μm.

[0012] The first plastic package body is also provided with a metal through hole, or a metal column penetrating from top to bottom.

[0013] Another technical solution provided by the present invention is: a packaging method for the above-mentioned single-sided copper-clad ceramic board, comprising the following steps:

[0014] S1, manufacturing a copper layer circuit board with a conductive circuit;

[0015] S2, printing, coating or placing low-temperature sintering material on the copper layer circuit board;

[0016] S3, placing the insulating thermally conductive ceramic substrate on the low-temperature sintering material for low-temperature sintering;

[0017] S4, plastic-sealing the entire semi-finished product obtained in S3 to form a first plastic-sealed body;

[0018] S5, removing the plastic packaging material on the outer surface of the insulating thermally conductive ceramic substrate to expose the outer surface of the insulating thermally conductive ceramic substrate.

[0019] Before step S2, the following pre-operation steps are also included:

[0020] S2.1, apply adhesive film to the outer surface of the copper layer circuit board and compact it;

[0021] S2.2, cleaning the surface of the copper layer circuit board;

[0022] Before step S3, the following pre-operation steps are also included:

[0023] S3.1, cleaning the surface of the insulating thermally conductive ceramic substrate;

[0024] Before step S4, the following pre-operation steps are also included:

[0025] S4.1, cleaning the surface of the semi-finished product obtained in S3; in step S4, the first plastic sealing body wraps all surfaces except one side of the film;

[0026] After step S5, the method further includes step S6: removing the adhesive film applied in step S2.1.

[0027] Among them, the method further includes step S5.1 between steps S5 and S6, grinding and opening millimeter-level micro grooves on the outer surface of the insulating thermally conductive ceramic substrate to increase the heat dissipation area of ​​the insulating thermally conductive ceramic substrate.

[0028] The third technical solution provided by the present invention is: a power module packaging structure, comprising a first single-sided copper-clad ceramic board, a second single-sided copper-clad ceramic board, a chip, and a second plastic package body, wherein the first single-sided copper-clad ceramic board and the second single-sided copper-clad ceramic board are the single-sided copper-clad ceramic boards described above, and the chip comprises a first pole and a second pole located on the front side, and a third pole located on the back side; the first single-sided copper-clad ceramic board, the chip, and the second single-sided copper-clad ceramic board are stacked up and down, and the second plastic package body is used to wrap the side surfaces of the first single-sided copper-clad ceramic board, the chip, and the second single-sided copper-clad ceramic board, and expose the first single-sided copper-clad ceramic board. The outer surface of the insulating thermally conductive ceramic substrate of the ceramic board and the second single-sided copper-clad ceramic board; the copper layer circuit board of the first single-sided copper-clad ceramic board is provided with a first circuit, a second circuit and a third circuit, and is also integrally formed or welded with a first output pin, a second output pin and a third output pin; the copper layer circuit board of the second single-sided copper-clad ceramic board is provided with a boss; the first electrode of the chip is connected to the first output pin through the first circuit, and the second electrode is connected to the second output pin through the second circuit; the third electrode is connected to the third output pin through the copper layer circuit board of the second single-sided copper-clad ceramic board, the boss and the third circuit in sequence.

[0029] Wherein, the chip is a field effect tube, the first pole is the D pole, the second pole is the G pole, and the third pole is the S pole; or the chip is an IGBT, the first pole is the E pole, the second pole is the G pole, and the third pole is the C pole.

[0030] The beneficial effects of the present invention are as follows: the present application provides a new single-sided copper-clad ceramic board, which no longer adopts the traditional sandwich-type symmetrical structure of upper and lower double-layer copper-clad boards to reduce the overall deformation and warping, but only sets a single-sided copper layer circuit board, and the structure is simpler. Low-temperature sintering (less than or equal to 300°C) is used instead of high-temperature welding (above 800°C) to reduce the overall deformation and warping caused by inconsistent thermal expansion, greatly reducing the process difficulty, and having fewer material bonding interfaces. Compared with the welding voids and welding delamination caused by two high temperatures, the defects are much reduced. At the same time, the number of processes and the processing materials used (solder, photosensitive adhesive, etching solution, cleaning solution) are also much less, the processing technology is simpler, the manufacturing cost is lower, and it is more suitable for large-scale production, with obvious overall advantages.

[0031] The manufacturing process of the copper layer circuit board of the present application is similar to the processing method of the lead frame. It is directly made by processes such as stamping, rather than etching. Compared with the two etchings of the original process, the process is greatly reduced, the process is simpler, the processing flexibility is stronger, the conductive circuit precision is higher, and the production cost is lower. It completely changes the current situation of using etching process to make conductive circuits on the existing double-sided copper-clad ceramic board. In batch production, it is produced and processed in units of the entire copper layer circuit board, with large batches and high production efficiency. The low-temperature sintering material as the intermediate bonding layer can not only quickly conduct heat and dissipate heat, but also improve the reliability of heat dissipation. When the temperature changes, it has better toughness, and plays a buffering role for the internal stress generated by the inconsistent deformation of the insulating thermal conductive ceramic substrate and the copper layer circuit board, reducing the risk of fracture and delamination of the intermediate bonding layer. The first plastic encapsulation body is used to wrap the side of the insulating thermal conductive ceramic substrate and the copper layer circuit board to improve the overall strength of the single-sided copper-clad ceramic board, while reducing the invasion of water vapor from the side, improving product reliability, and removing the plastic encapsulation material on the outer surface of the insulating thermal conductive ceramic substrate through post-processing, which is not only conducive to heat dissipation, but also can make the surface of the single-sided copper-clad ceramic board flat, which is conducive to subsequent other operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a top view of the first embodiment of the single-sided copper-clad ceramic board of the present invention;

[0033] Figure 2 yes Figure 1 Sectional view along the AA direction;

[0034] Figure 3 It is a schematic diagram of printing, coating or placing a low-temperature sintering material on a copper layer circuit board in Embodiment 1 of the single-sided copper-clad ceramic board packaging method of the present invention;

[0035] Figure 4 It is a schematic diagram of placing an insulating thermally conductive ceramic substrate on a low-temperature sintering material for low-temperature sintering in Embodiment 1 of the single-sided copper-clad ceramic board packaging method of the present invention;

[0036] Figure 5It is a schematic diagram of plastic sealing the semi-finished product obtained after sintering in the first embodiment of the packaging method of the single-sided copper-clad ceramic board of the present invention;

[0037] Figure 6 It is a schematic diagram of printing, coating or placing low-temperature sintering material on a copper layer circuit board in the mass production of the single-sided copper-clad ceramic board packaging method of the present invention;

[0038] Figure 7 It is a schematic diagram of placing an insulating thermally conductive ceramic substrate on a low-temperature sintering material in the mass production of the single-sided copper-clad ceramic board packaging method of the present invention;

[0039] Figure 8 It is a schematic diagram of the single-sided copper-clad ceramic board packaging method of the present invention after low-temperature sintering in mass production;

[0040] Fig. 9 It is a schematic diagram of the entire panel of the semi-finished product obtained after sintering in the batch production of the single-sided copper-clad ceramic board packaging method of the present invention after plastic sealing;

[0041] Fig.10 It is a schematic diagram of removing the plastic sealing material on the outer surface of the insulating thermal conductive ceramic substrate in the batch production of the single-sided copper-clad ceramic board packaging method of the present invention;

[0042] Fig.11 is a cross-sectional view of the second embodiment of the single-sided copper-clad ceramic board of the present invention;

[0043] Fig.12 It is a schematic diagram of the action of sequentially placing the low-temperature sintering material and the insulating thermal conductive ceramic substrate on the copper layer circuit board in the second embodiment of the single-sided copper-clad ceramic board of the present invention;

[0044] Fig.13 It is a schematic diagram of attaching an adhesive film to the outer surface of a copper layer circuit board in Embodiment 2 of the single-sided copper-clad ceramic board packaging method of the present invention;

[0045] Fig.14 It is a schematic diagram of printing, coating or placing a low-temperature sintering material on a copper layer circuit board in Embodiment 2 of the single-sided copper-clad ceramic board packaging method of the present invention;

[0046] Fig.15 It is a schematic diagram of placing the insulating thermally conductive ceramic substrate on the low-temperature sintering material for low-temperature sintering in the second embodiment of the single-sided copper-clad ceramic board packaging method of the present invention;

[0047] Fig.16 It is a schematic diagram of plastic sealing the semi-finished product obtained after sintering in the second embodiment of the packaging method of the single-sided copper-clad ceramic board of the present invention;

[0048] Fig.17It is a schematic diagram of removing the plastic encapsulation material on the outer surface of the insulating thermally conductive ceramic substrate in the second embodiment of the single-sided copper-clad ceramic board packaging method of the present invention;

[0049] Fig.18 It is a schematic diagram of the second embodiment of the single-sided copper-clad ceramic board packaging method of the present invention after microgrooving the outer surface of the insulating thermally conductive ceramic substrate;

[0050] Fig.19 is a top view of the third embodiment of the single-sided copper-clad ceramic board of the present invention;

[0051] Fig. 20 is a bottom view of the third embodiment of the single-sided copper-clad ceramic board of the present invention;

[0052] Fig.21 yes Fig.19 Cross-section along the middle BB direction;

[0053] Fig. 22 is a cross-sectional schematic diagram of the chip of the present invention;

[0054] Fig.23 is a top view of an embodiment of the power module packaging structure of the present invention;

[0055] Fig.24 yes Fig.23 Cross-section along the mid-CC direction;

[0056] Fig.25 is a schematic diagram of the assembly action of the power module packaging structure embodiment of the present invention;

[0057] Fig.26 is a schematic diagram of the assembled structure of the power module packaging structure embodiment of the present invention;

[0058] Fig. 27 It is a front view of the first single-sided copper-clad ceramic board in the embodiment of the power module packaging structure of the present invention;

[0059] Fig.28 It is a front view of the second single-sided copper-clad ceramic board in the embodiment of the power module packaging structure of the present invention;

[0060] Fig.29 It is a schematic diagram of the matching relationship between the first single-sided copper-clad ceramic board and the chip in the embodiment of the power module packaging structure of the present invention;

[0061] Fig.30 It is a schematic diagram of the matching relationship between the second single-sided copper-clad ceramic board and the chip in the power module packaging structure embodiment of the present invention.

[0062] Among them, 1. Insulating thermally conductive ceramic substrate; 11. Micro groove; 2. Copper layer circuit board; 21. Boss; 3. First plastic package; 31. Metal column; 4. Low temperature sintering material; 5. Adhesive film; 100. First single-sided copper-clad ceramic board; 101. First circuit; 102. Second circuit; 103. Third circuit; 104. First output pin; 105. Second output pin; 106. Third output pin; 200. Second single-sided copper-clad ceramic board; 300. Chip; 301. First pole; 302. Second pole; 303. Third pole; 400. Second plastic package; 500. First prefabricated solder sheet; 600. Second prefabricated solder sheet. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0064] As an embodiment 1 of the single-sided copper-clad ceramic plate of the present invention, Figures 1 to 5 As shown, it includes an insulating thermally conductive ceramic substrate 1, a copper layer circuit board 2 and a first plastic package 3. The insulating thermally conductive ceramic substrate 1 and the copper layer circuit board 2 are sintered into one body by a low-temperature sintering material 4. The first plastic package 3 wraps the sides of the insulating thermally conductive ceramic substrate 1 and the copper layer circuit board 2.

[0065] In this embodiment, the low-temperature sintering material 4 can be sintered silver, sintered copper, solder paste, prefabricated tin sheet or non-conductive heat dissipation glue, and the sintering temperature of these materials is below 300° C. Sintered silver and sintered copper are preferred. The insulating thermal conductive ceramic substrate 1 material can be selected from AI2O3, AIN, AISiC, etc.

[0066] In this embodiment, the layer thickness of the low-temperature sintering material 4 is 30-80 μm, so as to avoid insufficient thickness of the low-temperature sintering material 4 and excessive overflow of the low-temperature sintering material 4 .

[0067] The packaging method of the single-sided copper-clad ceramic board described in this embodiment includes the following steps:

[0068] S1, manufacturing a copper layer circuit board 2 having a conductive circuit;

[0069] S2, reference Figure 3 and Figure 6 , printing, coating or placing a low-temperature sintering material 4 on the copper layer circuit board 2;

[0070] S3, refer to Figure 4 and Figure 7 , placing the insulating thermally conductive ceramic substrate 1 on the low-temperature sintering material 4 and performing low-temperature sintering to obtain Figure 8The semi-finished product shown can be sintered in a vacuum oven.

[0071] S4, ref. Figure 5 and Fig. 9 , the semi-finished product obtained in S3 is plastic-sealed in its entirety to form a first plastic-sealed body 3; the thickness of the plastic-sealed material covering the outer surface of the insulating thermally conductive ceramic substrate 1 is generally less than 100 μm to reduce the workload of subsequent removal;

[0072] S5, removing the plastic sealing material on the outer surface of the insulating thermally conductive ceramic substrate 1 to expose the outer surface of the insulating thermally conductive ceramic substrate 1, referring to Figure 2 Finally, the single-sided copper-clad ceramic board is cut into individual pieces.

[0073] In this embodiment, the overall plastic sealing of the entire page in step S4 refers to the integrated plastic sealing of the entire page product, and the single product does not have an independent plastic sealing body. The advantage of this is that as long as the size of the entire page is the same and the packaging thickness is consistent, the plastic sealing mold can be universal, which can save mold opening costs; in addition, since the plastic sealing no longer distinguishes between single products, there is no need to press the connecting ribs between single products, the plastic sealing mold structure is simpler, and the plastic sealing yield rate is higher. When cutting the single-sided copper-clad ceramic board into a single body, the plastic sealing material and the connecting ribs in the middle can be cut off together.

[0074] The present application provides a new single-sided copper-clad ceramic board, which no longer adopts the traditional sandwich-type symmetrical structure of upper and lower double-layer copper-clad boards to reduce overall deformation and warping, but only sets a single-sided copper layer circuit board 2, which has a simpler structure and reduces the overall deformation and warping caused by inconsistent thermal expansion by low-temperature sintering (less than or equal to 300°C) instead of high-temperature welding (above 800°C), greatly reducing the process difficulty, fewer material bonding interfaces, and much less defects such as welding voids and welding delamination caused by two high temperatures. At the same time, the number of processes and the processing materials used (solder, photosensitive glue, etching solution, cleaning solution) are also much less, the processing technology is simpler, the manufacturing cost is lower, and it is more suitable for large-scale production, with obvious overall advantages.

[0075] The manufacturing process of the copper layer circuit board 2 of the present application is similar to the processing method of the lead frame. It is directly manufactured through processes such as stamping, rather than etching. Compared with the two etchings of the original process, the number of processes is greatly reduced, the process is simpler, the processing flexibility is stronger, the conductive circuit accuracy is higher, and the manufacturing cost is lower. It completely changes the current situation of using etching process to manufacture conductive circuits on the existing double-sided copper-clad ceramic board. In batch production, the production and processing are carried out according to the whole copper layer circuit board 2, with large batches and high production efficiency. The low-temperature sintered material 4 as the intermediate bonding layer can not only conduct heat and dissipate heat quickly, and improve the reliability of heat dissipation, but also has better toughness when the temperature changes, and plays a buffering role for the internal stress caused by the inconsistent deformation of the insulating thermal conductive ceramic substrate 1 and the copper layer circuit board 2, thereby reducing the risk of fracture and delamination of the intermediate bonding layer. The first plastic packaging body 3 is used to wrap the sides of the insulating thermally conductive ceramic substrate 1 and the copper layer circuit board 2 to improve the overall strength of the single-sided copper-clad ceramic board, while reducing the invasion of water vapor from the side and improving product reliability. The plastic packaging material on the outer surface of the insulating thermally conductive ceramic substrate 1 is removed through post-processing, which is not only beneficial to heat dissipation, but also can make the surface of the single-sided copper-clad ceramic board flat, which is beneficial to subsequent other operations.

[0076] As a second embodiment of the single-sided copper-clad ceramic plate of the present invention, Figures 11 to 18 As shown, the difference from Example 1 is that the copper layer circuit board 2 is also provided with a boss 21 (which can also be designed as a groove). Compared with the original process, it has stronger flexibility and can process a copper layer circuit board 2 with an integrally formed boss 21 or a groove structure. In this way, the copper layer circuit board 2 is no longer a flat circuit pattern, and the boss 21 can be used as a copper column to realize some three-dimensional circuit connection functions.

[0077] The packaging method of the single-sided copper-clad ceramic board described in this embodiment includes the following steps:

[0078] S1, manufacturing a copper layer circuit board 2 with a conductive circuit, wherein a boss 21 with a required height and shape is provided on the copper layer circuit board 2;

[0079] S2.1, reference Fig.13 , a glue film 5 is pasted on the outer surface of the copper layer circuit board 2 and compacted to keep one side of the boss 21 flat; the preferred relationship between the thickness H1 of the glue film 5 and the height T1 of the boss 21 is H1-T1>50μm-100μm; a special support plate with grooves can also be used in this step, and the same effect can be achieved by spraying glue and baking and curing, but the subsequent process requires the use of chemical solutions to separate the support plate, the steps will be more complicated, and the cost will also increase.

[0080] S2.2, cleaning the surface of the copper layer circuit board 2 to remove dirt and impurities on the surface;

[0081] S2, reference Fig.14 , printing or coating a low-temperature sintering material 4 on the copper layer circuit board 2;

[0082] S3.1, cleaning the surface of the insulating thermally conductive ceramic substrate 1;

[0083] S3, refer to Fig.15 , placing the insulating thermally conductive ceramic substrate 1 on the low-temperature sintering material 4 for low-temperature sintering;

[0084] S4.1, cleaning the surface of the semi-finished product obtained in S3;

[0085] S4, ref. Fig.16 , plastic-sealing the semi-finished product obtained in S3 to form a first plastic-sealed body 3, wherein the first plastic-sealed body 3 covers all surfaces except one side of the adhesive film 5;

[0086] S5, refer to Fig.17 , removing the plastic sealing material on the outer surface of the insulating thermally conductive ceramic substrate 1 to expose the outer surface of the insulating thermally conductive ceramic substrate 1, which can be specifically done by grinding or punching and milling;

[0087] S5.1, refer to Fig.18 , millimeter-scale micro grooves 11 are ground on the outer surface of the insulating thermally conductive ceramic substrate 1 to increase the heat dissipation area of ​​the insulating thermally conductive ceramic substrate 1 and improve the heat dissipation capacity;

[0088] S6: removing the adhesive film 5 attached in step S2.1.

[0089] The surface cleaning described in this embodiment is preferably plasma cleaning. This method better ensures the surface cleanliness of the copper layer circuit board and will not be covered by the plastic packaging material; it fully utilizes the flexibility of the film 5, better solves the avoidance problem of the boss 21, and reduces the risk of deformation of the boss 21.

[0090] As the third embodiment of the single-sided copper-clad ceramic plate of the present invention, Figures 19 to 21 As shown, the difference from the first embodiment is that the first plastic package body 3 is further provided with a metal column 31 (metal through holes can also be provided) that runs through the first plastic package body 3. Since the insulating thermally conductive ceramic substrate 1 has a high hardness and it is difficult to process through holes, it is difficult to achieve the purpose of the metal circuit running through the first plastic package body 3. In this embodiment, the metal column 31 that runs through the first plastic package body 3 is provided, which fully utilizes the advantage of the high plasticity of the first plastic package body 3.

[0091] IGBT / MOSFET power modules are widely used in various energy fields, especially new energy vehicles. When the power module is running at high power and high current, the chip inside the power module will generate a lot of heat, which must be dissipated in time. Otherwise, the chip temperature will rise too high, resulting in unstable chip performance and even direct damage and failure of the chip.

[0092] like Fig. 22As shown, the chip 300 described in the present application includes a first pole 301 and a second pole 302 located on the front side, and a third pole 303 located on the back side.

[0093] As an embodiment of the power module packaging structure described in this application, Figures 23 to 30 As shown, it includes a first single-sided copper-clad ceramic board 100, a second single-sided copper-clad ceramic board 200, a chip 300 and a second plastic package 400, wherein the first single-sided copper-clad ceramic board 100 and the second single-sided copper-clad ceramic board 200 are the single-sided copper-clad ceramic boards described above. The first single-sided copper-clad ceramic board 100, the chip 300 and the second single-sided copper-clad ceramic board 200 are stacked up and down, and the second plastic package 400 is used to wrap the side surfaces of the first single-sided copper-clad ceramic board 100, the chip 300 and the second single-sided copper-clad ceramic board 200, and expose the outer surfaces of the insulating and thermally conductive ceramic substrates of the first single-sided copper-clad ceramic board 100 and the second single-sided copper-clad ceramic board 200.

[0094] like Fig.29 and Fig.30 As shown, the copper layer circuit board of the first single-sided copper-clad ceramic board 100 is provided with a first circuit 101, a second circuit 102 and a third circuit 103, and is also integrally formed or welded with a first output pin 104, a second output pin 105 and a third output pin 106; the copper layer circuit board of the second single-sided copper-clad ceramic board 200 is provided with a boss 21; the first pole 301 of the chip 300 is connected to the first output pin 104 through the first circuit 101, and the second pole 302 is connected to the second output pin 105 through the second circuit 102; the third pole 303 is connected to the third output pin 106 through the copper layer circuit board 2 of the second single-sided copper-clad ceramic board 200, the boss 21 and the third circuit 103 in sequence.

[0095] In this embodiment, if Fig.23 and Fig.24 As shown, there are two chips 300 arranged horizontally in parallel. The chips 300 can be basically understood as being in a parallel relationship, and the current capacity can be improved by increasing the number of chips.

[0096] In this embodiment, the chip 300 is a field effect transistor, the first pole 301 is a D pole, the second pole 302 is a G pole, and the third pole 303 is an S pole; or the chip 300 is an IGBT, the first pole 301 is an E pole, the second pole 302 is a G pole, and the third pole 303 is a C pole. The chip 300 can be a GaN chip or a SiC chip. GaN chips or SiC chips are power chips with high heat dissipation requirements, and the packaging structure described in the present invention has more obvious advantages in electrical performance and heat dissipation.

[0097] The power module packaging structure of the present application forms a double-sided heat dissipation structure, which has the advantages of more stable performance, better heat dissipation, lower power consumption, higher reliability and longer service life. The third pole 303 of the chip 300 is connected to the copper layer circuit board 2 of the first single-sided copper-clad ceramic board 100 through the copper layer circuit board 2 and the boss 21 of the second single-sided copper-clad ceramic board 200. There is no need to set structures such as copper columns and copper bosses, which optimizes the circuit connection structure. The traditional multi-structure welding of metal wires or metal sheets is eliminated, the line transmission path is shortened, the parasitic inductance and line power consumption of the product are greatly reduced, the heat transfer medium is reduced, and the heat dissipation effect is improved. The output pin can be integrally formed with the copper layer circuit board 2 of the first single-sided copper-clad ceramic board 100, or it can be electrically connected to the copper layer circuit board 2 by welding. The size of the output pin is designed to match the current it is to carry.

[0098] The first plastic package body 3 and the second plastic package body 400 have the same characteristics and good bonding strength, providing higher reliability and stability for the power module packaging structure. The present application can simplify the welding process, reduce the welding tilt problem, simplify the packaging process, reduce component materials, and reduce product costs by preferably using the first prefabricated solder sheet 500 and the second prefabricated solder sheet 600 to weld the first single-sided copper-clad ceramic board 100, the second single-sided copper-clad ceramic board 200 and the chip 300.

[0099] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A single-sided copper-clad ceramic plate, characterized in that: It comprises an insulating thermally conductive ceramic substrate, a copper layer circuit board and a first plastic package body, wherein the insulating thermally conductive ceramic substrate and the copper layer circuit board are sintered into one body by means of a low temperature sintering material, and the first plastic package body wraps the sides of the insulating thermally conductive ceramic substrate and the copper layer circuit board.

2. The single-sided copper-clad ceramic board according to claim 1, characterized in that: The copper layer circuit board is also provided with a boss or a groove.

3. The single-sided copper-clad ceramic board according to claim 1, characterized in that: The low-temperature sintering material is sintered silver, sintered copper, solder paste, prefabricated tin sheet or non-conductive heat dissipation glue.

4. The single-sided copper-clad ceramic board according to claim 3, characterized in that: The layer thickness of the low-temperature sintering material is 30-80 μm.

5. The single-sided copper-clad ceramic board according to claim 1, characterized in that: The first plastic package body is also provided with a metal through hole, or a metal column penetrating from top to bottom.

6. A packaging method for the single-sided copper-clad ceramic board according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1, manufacturing a copper layer circuit board with a conductive circuit; S2, printing, coating or placing low-temperature sintering material on the copper layer circuit board; S3, placing the insulating thermally conductive ceramic substrate on the low-temperature sintering material for low-temperature sintering; S4, plastic-sealing the entire semi-finished product obtained in S3 to form a first plastic-sealed body; S5, removing the plastic packaging material on the outer surface of the insulating thermally conductive ceramic substrate to expose the outer surface of the insulating thermally conductive ceramic substrate.

7. The packaging method of the single-sided copper-clad ceramic board according to claim 6, characterized in that: Before step S2, the following pre-operation steps are also included: S2.1, apply adhesive film to the outer surface of the copper layer circuit board and compact it; S2.2, cleaning the surface of the copper layer circuit board; Before step S3, the following pre-operation steps are also included: S3.1, cleaning the surface of the insulating thermally conductive ceramic substrate; Before step S4, the following pre-operation steps are also included: S4.1, cleaning the surface of the semi-finished product obtained in S3; in step S4, the first plastic sealing body wraps all surfaces except one side of the film; After step S5, the method further includes step S6: removing the adhesive film applied in step S2.

1.

8. The packaging method of the single-sided copper-clad ceramic board according to claim 7, characterized in that: The method further includes step S5.1 between steps S5 and S6, wherein millimeter-scale micro grooves are ground on the outer surface of the insulating thermally conductive ceramic substrate to increase the heat dissipation area of ​​the insulating thermally conductive ceramic substrate.

9. A power module packaging structure, characterized in that: The invention comprises a first single-sided copper-clad ceramic board, a second single-sided copper-clad ceramic board, a chip and a second plastic package, wherein the first single-sided copper-clad ceramic board and the second single-sided copper-clad ceramic board are the single-sided copper-clad ceramic boards according to any one of claims 1 to 5, and the chip comprises a first pole and a second pole located on the front side, and a third pole located on the back side; the first single-sided copper-clad ceramic board, the chip and the second single-sided copper-clad ceramic board are stacked up and down, and the second plastic package is used to wrap the first single-sided copper-clad ceramic board, the chip and the second single-sided copper-clad ceramic board, and expose the outer surface of the insulating thermal conductive ceramic substrate of the first single-sided copper-clad ceramic board and the second single-sided copper-clad ceramic board; The copper layer circuit board of the first single-sided copper-clad ceramic board is provided with a first circuit, a second circuit and a third circuit, and is also integrally formed or welded with a first output pin, a second output pin and a third output pin; the copper layer circuit board of the second single-sided copper-clad ceramic board is provided with a boss; the first pole of the chip is connected to the first output pin through the first circuit, and the second pole is connected to the second output pin through the second circuit; the third pole is connected to the third output pin through the copper layer circuit board of the second single-sided copper-clad ceramic board, the boss and the third circuit in sequence.

10. The power module packaging structure according to claim 9, characterized in that: The chip is a field effect tube, the first pole is the D pole, the second pole is the G pole, and the third pole is the S pole; or the chip is an IGBT, the first pole is the E pole, the second pole is the G pole, and the third pole is the C pole.

Images