Manufacturing method of power module with double-layer packaging structure

Abstract

The invention discloses a manufacturing method of a power module with a double-layer packaging structure, and belongs to the field of semiconductor power modules, an aluminate inorganic gelling composite material is used as an inner packaging layer, the material can tolerate a chip junction temperature higher than 240 DEG C, the problem that a traditional packaging material is not resistant to high temperature is solved, and the power module with the double-layer packaging structure is manufactured. The inorganic cementing material is reinforced by using a fiber material; the nanometer reinforced organic composite material is encapsulated and cured outside the fiber reinforced inorganic composite inner packaging layer to form the integrally formed shell, the air tightness problem of the power module is solved, and meanwhile, the integrated nanometer reinforced organic composite outer packaging layer replaces a traditional split plastic shell, so that the power module has the characteristics of impact resistance and high strength. According to the method provided by the invention, the power module with a double-layer packaging structure can be manufactured, and the power module manufactured by the method provided by the invention uses the double-layer packaging structure to replace a traditional packaging material and a plastic shell, and has the characteristics of high strength, impact resistance and suitability for a high junction temperature power chip.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor power modules and relates to a power module with a double-layer packaging structure. Background Art

[0002] With the development of power electronic systems in recent years, the performance of traditional silicon-based semiconductors has been gradually exploited to the limit. Driven by various challenges and practical demands, the rise of third-generation semiconductors is irresistible. Among the third-generation semiconductors, silicon carbide has been widely used in many fields due to its high breakdown field strength, high temperature resistance, and high operating frequency. In the field of power modules, silicon carbide MOSFET power modules have begun to partially replace traditional silicon-based IGBT modules. However, the higher power density that silicon carbide chips can achieve poses a severe test to the packaging materials, and the inapplicability of the original packaging solutions has become a bottleneck restricting the progress of third-generation semiconductor devices.

[0003] The potting materials of traditional power modules usually use silica gel and epoxy resin. However, as organic substances, they both have inherent defects: they are not resistant to high temperatures, and usually need to be modified to improve the temperature resistance of organic potting materials. Most of the traditional organic potting materials on the market usually have an operating temperature below 200°C, which is difficult to meet the temperature resistance requirements of future high-power third-generation wide-bandgap semiconductor power modules. The chip junction temperature of third-generation wide-bandgap semiconductors can reach above 200°C, and even the highest temperature can reach 250°C. Therefore, finding a high-temperature-resistant packaging material is an important part of developing higher-performance power modules. For this reason, some researchers in related industries have shifted their attention to the field of inorganic materials.

[0004] The present invention adopts an inorganic-organic double-layer packaging structure, encapsulates the chip surface with a fiber-reinforced inorganic cementitious composite material, which can withstand a chip junction temperature higher than 240°C during use. At the same time, the fiber material and the inorganic cementitious material are compounded to prevent the encapsulation layer from cracking. The present invention potting a layer of organic composite material on the surface of the inorganic cementitious material and integrally curing it into a packaging shell, which solves the airtightness problem of the power module. The present invention uses an integrally potted and formed shell to replace the traditional split-type packaging shell, which has the characteristics of high strength and impact resistance. And the present invention adds nano-fillers to the organic material to enhance the organic material, thereby improving the ability of the power module to resist external physical impacts and ensuring the long-term stable operation of the power module. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a manufacturing method of a power module with a double-layer packaging structure, which can manufacture a power module that can carry a higher power density and withstand a higher chip junction temperature.

[0006] To solve the above problems, the present invention provides a method for manufacturing a power module with a double-layer encapsulation structure, which is characterized in that the main component structure of the prepared power module with a double-layer encapsulation structure includes: a bottom plate, a nano-enhanced organic composite outer encapsulation layer, a copper-clad ceramic substrate, a chip, a metal terminal, an electrical interconnection structure, and a fiber-reinforced inorganic composite inner encapsulation layer. The manufacturing steps include: S01, Chip dicing and mounting: After dicing the whole wafer, a single chip is obtained. Clean the surface of the copper-clad ceramic substrate and weld the chip to the designed position on the surface of the copper-clad ceramic substrate through silver sintering or copper sintering process; S02, Interconnection bonding: Use a bonding machine to construct an electrical interconnection structure on the surface of the copper-clad ceramic substrate and the surface of the chip; S03, Welding of copper-clad ceramic substrate: Weld the copper-clad ceramic substrate to the designed position on the surface of the bottom plate through a vacuum reflow soldering process; S04, Fixing the terminal: Use ultrasonic welding to weld the metal terminal to the designed position; S05, Secondary interconnection bonding: Use a bonding machine to construct an electrical interconnection structure on the surface of the terminal and the copper-clad ceramic substrate; S06, Preparation of inorganic cementitious material powder: Mix alumina powder, calcium hydroxide powder, and water evenly, press them into blocks, and heat them to 1280 - 1350°C at a heating rate of 1 - 10°C / minute. After sintering treatment at 1280 - 1350°C for 30 - 120 minutes, take out the sintered product and ball mill it into powder to make inorganic cementitious material powder; S07, Preparation of inorganic cementitious composite: Mix water and fiber material, mechanically disperse them, and then mix them with inorganic cementitious material powder and a retarder. After stirring, perform vibration defoaming treatment to make an inorganic cementitious composite slurry; S08, Inorganic cementitious composite potting: Assemble the inner encapsulation layer mold with the module manufactured in step S05, and pour the inorganic cementitious material slurry prepared in step S07 into the module under a vacuum degree of -0.08 to -0.09 MPa; S09, Primary heating of inorganic cementitious composite: Heat the potted module at a humidity of 35% - 90% to cure the inorganic cementitious composite; S10, Secondary heating of inorganic cementitious composite: Heat the module processed in step S09 under a vacuum degree of -0.09 to -0.097 MPa to evaporate the free water in the inorganic cementitious composite; S11, Preparation of organic composite: Mix nano-filler powder with a resin mixture. The resin mixture refers to a mixture of a resin matrix, a curing agent, and a surfactant. After mixing the filler powder with the resin mixture, mechanically stir to obtain a flowable organic composite slurry, and perform vacuum defoaming treatment; S12, potting of organic composite materials: the inner packaging layer mold described in S08 is removed and replaced with an outer packaging layer mold, and the organic composite material slurry prepared in step S11 is poured into the module treated in step S10 under a vacuum degree of -0.08 to -0.09 MPa; S13, curing of the organic composite material: heating and curing the power module encapsulated in step S12, and removing the outer packaging layer mold in S12 after the curing is completed, to obtain a power module with a double-layer packaging structure; Furthermore, it is characterized in that the raw materials of the preparation method of the inorganic gelling material powder in step S06 are calculated by weight: 50 to 100 parts of aluminum oxide powder, 110 to 260 parts of calcium hydroxide powder, and 10 to 50 parts of water; the obtained inorganic gelling material powder component is tricalcium aluminate.

[0007] Furthermore, it is characterized in that in the step S06, the particle size of the aluminum oxide powder is 5 to 50 microns; the particle size of the calcium hydroxide powder is 20 to 50 microns; and the particle size of the inorganic gelling material powder is 0.5 to 30 microns.

[0008] Furthermore, it is characterized in that the raw materials of the preparation method of the inorganic gelling composite material slurry in step S07 are calculated by weight: 6 to 10 parts of water, 0.02 to 0.05 parts of fiber, 0 to 0.2 parts of retarder, and 15 to 30 parts of inorganic gelling material powder; the fiber is one or more of glass fiber, basalt fiber, polyimide fiber, and alumina fiber; the fiber diameter is 5 to 50 microns and the length is 0.1 to 5 mm.

[0009] Furthermore, it is characterized in that, in the one heating process in step S09, the temperature is maintained at 50° C. to 85° C. and the insulation time is 120 to 1440 minutes.

[0010] Furthermore, it is characterized in that, in the secondary heating process in step S10, the temperature is maintained at 80-105° C., the insulation time is 120-1440 minutes, and the inorganic gelling material components after the secondary heating include tricalcium aluminate hexahydrate, fiber, and tricalcium aluminate.

[0011] Further, it is characterized in that the raw materials of the organic composite material slurry in the S11 step are calculated by mass fraction: 80 to 120 parts of resin matrix, 20 to 50 parts of curing agent, 0.5 to 2 parts of surfactant, 0.1 to 2 parts of accelerator, and 2.5 to 10 parts of nano-filler powder; the nano-filler powder is one or more of nano-zirconium oxide powder, nano-silicon dioxide powder, nano-aluminum nitride powder, nano-alumina powder, and nano-boron nitride powder; the particle size of the nano-filler powder is 10 to 50 nanometers, and the morphology is one or more of spherical, angular, elliptical, flaky, and rod-shaped; the resin matrix is epoxy resin.

[0012] The power module has the characteristics of high strength and high junction temperature resistance, and has the following advantages compared with the prior art: 1. The present invention uses an aluminate inorganic cementitious composite material as the inner encapsulation layer. This material can withstand a chip junction temperature higher than 240°C, solves the problem that traditional encapsulation materials are not heat-resistant, enables the chip performance to no longer be restricted by the encapsulation material, and uses a fiber material to reinforce the inorganic cementitious material to prevent the encapsulation layer from cracking.

[0013] 2. The present invention uses a nano-enhanced organic composite material to integrally form a shell outside the fiber-reinforced inorganic composite inner encapsulation layer, solves the airtightness problem of the power module, and at the same time uses a nano-enhanced organic composite outer encapsulation layer to replace the traditional split plastic shell, making the power module have the characteristics of shock resistance and high strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Attached Figure 1 Shown is a schematic diagram of the manufacturing process of the power module with a double-layer encapsulation structure according to the present invention.

[0015] Attached Figure 2 Shown is a schematic diagram of the structure of the power module with a double-layer encapsulation structure according to the present invention, where (a) is a schematic diagram of the appearance of the power module, (b) is an exploded view of the internal structure of the power module, and (c) is a schematic diagram of the cross-sectional structure of the power module.

[0016] Attached Figure 3 Shown is a schematic diagram of the potting process of the fiber-reinforced inorganic cementitious composite material according to the present invention, where (a) is a schematic diagram of the structure of the inner encapsulation layer mold, (b) is a schematic diagram of the assembly structure of the inner encapsulation layer mold and the module semi-finished product, (c) is a schematic diagram of the potting and curing process of the fiber-reinforced inorganic cementitious composite material, and (d) is a schematic diagram of the semi-finished power module obtained by removing the inner encapsulation layer mold.

[0017] Attached Figure 4 Shown is a schematic diagram of the potting process of the nano-enhanced organic composite material according to the present invention, where (a) is a schematic diagram of the structure of the outer encapsulation layer mold, (b) is a schematic diagram of the assembly structure of the outer encapsulation layer mold and the module semi-finished product, (c) is a schematic diagram of the potting and curing process of the nano-enhanced organic composite material, and (d) is a schematic diagram of the power module with a double-layer encapsulation structure obtained by removing the outer encapsulation layer mold.

[0018] Attached Figure 5 Shown is a thermal analysis curve diagram of the inorganic cementitious composite material according to the present invention.

[0019] Attached Figure 6Shown is a comparison diagram of the XRD of the inorganic cementitious material and the inorganic cementitious material powder prepared in Specific Example 1 with the standard card. Among them, (a) is the comparison diagram of the XRD of the inorganic cementitious material powder with the tricalcium aluminate standard card, and (b) is the comparison diagram of the XRD of the inorganic cementitious material with the tricalcium aluminate hexahydrate and tricalcium aluminate standard cards. Detailed implementation manners

[0020] The specific embodiments of the present invention will be described in detail below. It should be noted that the embodiments described here are only for illustrative purposes and are not used to limit the present invention. In the following description, in order to provide a thorough understanding of the present invention, a large number of specific details are set forth. However, it will be apparent to those of ordinary skill in the art that the present invention does not have to employ these specific details. In other instances, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the present invention.

[0021] Throughout the specification, the reference to "an embodiment", "embodiment", "an example", or "example" means that the specific features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment of the present invention. Thus, the phrases "in an embodiment", "in embodiments", "an example", or "example" appearing throughout the specification do not necessarily all refer to the same embodiment or example. Furthermore, the specific features, structures, or characteristics may be combined in any suitable combination and / or sub-combination in one or more embodiments or examples. The present invention will be specifically described below with reference to the accompanying drawings.

[0022] In the following description of the technical solution of the present invention with reference to the accompanying drawings, the dimensions, proportions, and positional relationships of the various elements in the drawings are only exemplary, and the connection manners between the illustrated elements are also only for illustration, and none of them are used to limit the present invention.

[0023] Embodiment

[0024] The said example illustrates the application of the manufacturing method of the power module with a double-layer encapsulation structure in the manufacturing of a silicon carbide MOSFET power module.

[0025] Refer to the attached Figure 2 , the manufactured silicon carbide MOSFET power module has the following main structures: a bottom plate 101, an active metal brazing substrate 102, a chip 103, a metal lead 104, a fiber-reinforced inorganic composite inner encapsulation layer 105, a nano-enhanced organic composite outer encapsulation layer 106, and a metal terminal 107; Refer to the attached Figure 3 in (a), the inner encapsulation mold has the following main structures: an inner encapsulation layer mold section A 201, an inner encapsulation layer mold section B 202, a terminal through hole 203, and a bottom plate groove 204; Refer to the attached Figure 4In (a) of the figure, the outer encapsulation mold has the following main structures: outer encapsulation layer mold section A 301, outer encapsulation layer mold section B 302, and terminal through-holes 303.

[0026] Refer to the appendix Figure 1 , and perform a series of steps from S01 chip slicing and mounting to the curing of S13 organic composite material to obtain a power module with a double-layer encapsulation structure.

[0027] S01, Chip slicing and mounting: First, clean the surface of the active metal brazing substrate 102, remove oxides and contaminants, and evenly coat the designed area of the active metal brazing substrate with sintered copper paste by screen printing; cut the whole wafer to obtain chips 103, and use a chip mounter to accurately mount the chips 103 on the copper paste-coated area of the active metal brazing substrate 102; treat the active metal brazing substrate 102 with the mounted chips at 150 °C for 10 minutes to dry the copper paste and remove organic solvents, forming a preliminary copper particle accumulation layer. During the process, introduce nitrogen as a protective atmosphere to prevent copper particle oxidation; then perform high-temperature sintering in a hot-press sintering furnace: set the working temperature at 275 °C, the working time at 5 minutes, the working pressure at 25 MPa, and introduce nitrogen as a protective atmosphere to achieve densification sintering of copper particles.

[0028] S02, Interconnection bonding: Use a bonding machine to complete the bonding work of the metal leads 104 on the surfaces of the chips 103 and the active metal brazing substrate 102 by ultrasonic wire bonding process, and use ultrasonic waves to clean the metal pins.

[0029] S03, Welding of the active metal brazing substrate: Clean the surface of the bottom plate 101, remove oxides and contaminants, and after mounting the active metal brazing substrate 102 that has completed the bonding work and the solder sheet on the surface of the bottom plate 101, send it into a vacuum reflow furnace, introduce nitrogen as a protective atmosphere, and gradually heat up to 245 °C; start vacuum pumping at 245 °C, maintain the vacuum degree at -0.0995 MPa for 60 seconds, and then return to normal temperature and pressure.

[0030] S04, Fixing the terminals: Weld the metal terminals 107 in place with an ultrasonic soldering gun.

[0031] S05, Secondary interconnection bonding: Use a bonding machine to complete the electrical interconnection work between the metal terminals 107 and the active metal brazing substrate 102 on the surface of the active metal brazing substrate 102 by ultrasonic wire bonding process.

[0032] S06. Prepare an inorganic cementitious material powder. Mix alumina powder with a particle size of 45 μm, calcium hydroxide powder with a particle size of 30 μm, and water in a mass ratio of 10:20:8, stir evenly, press into blocks, place in a muffle furnace, heat at a heating rate of 3 °C per minute to a temperature of 1350 °C, hold for 30 minutes, take out the sintered product, crush it, and then put it into a ball mill jar for ball milling to obtain an inorganic cementitious material powder with an average particle size of 5 μm. As can be seen from (a) in the appendix Figure 6 the prepared powder is composed of tricalcium aluminate.

[0033] S07. Prepare an inorganic cementitious material. Mix polyimide fibers with a diameter of 20 μm and a length of 1 mm and water in a mass ratio of 1:20, and mechanically disperse for 10 minutes to obtain a polyimide fiber aqueous dispersion. Mix tricalcium aluminate powder, the polyimide fiber aqueous dispersion, and borax in a mass ratio of 20:9:0.3, and vibrate to remove bubbles.

[0034] S08. Encapsulation of the inorganic cementitious composite material. The specific process is as shown in the appendix Figure 3 Assemble the A section 201 of the inner encapsulation layer mold and the B section 202 of the inner encapsulation layer mold with the module manufactured in S01 - S05. Use a vacuum gluing machine to fill the inorganic cementitious material slurry prepared in S07 into the module manufactured in steps S01 - S05 at a gluing speed of 100 ml / min under a vacuum degree of -0.085 MPa.

[0035] S09. Primary heating of the inorganic cementitious composite material. Heat the module after encapsulation in S07 at 60 °C and 50% humidity for 12 hours.

[0036] S10. Secondary heating of the inorganic cementitious composite material. Heat the module after treatment in S08 at 95 °C and a vacuum degree of -0.095 MPa for 24 hours. After curing, obtain a fiber-reinforced inorganic composite inner encapsulation layer 105. As can be seen from (b) in the appendix Figure 6 the main component of the inorganic cementitious composite material after secondary heating is tricalcium aluminate hexahydrate.

[0037] S11. Composite material preparation: Mix an aromatic epoxy resin with a glass transition temperature greater than 185 °C, a curing agent, a surfactant, and an accelerator in a ratio of 100:30:1:1, mechanically stir at room temperature for 5 minutes, then mix spherical nano-alumina powder with a particle size of 30 nm and the resin mixture in a mass ratio of 1:25, and perform vacuum degassing treatment.

[0038] S12. Encapsulation of the organic composite material. The specific process is as shown in the appendix Figure 4As shown, after removing the inner encapsulation layer mold section A 201 and the inner encapsulation layer mold section B 202 described in S08 and assembling the outer encapsulation layer mold section A 301, the outer encapsulation layer mold section B 302 with the module, using a vacuum resin filling machine at a vacuum degree of -0.085 MPa and a resin filling speed of 35 ml / minute, the organic composite material slurry prepared in S11 is filled into the module encapsulated with inorganic materials that have undergone S08 to S10 treatment.

[0039] S13, curing of the organic composite material. After the module encapsulated in S12 is pre-cured at 95°C for 2 hours and then cured at 160°C for 2 hours, the resin cross-links and cures to obtain the nano-reinforced organic composite outer encapsulation layer 106. After the curing is completed, the outer encapsulation layer mold section A 301 and the outer encapsulation layer mold section B 302 described in S12 are removed, and a power module with a double-layer encapsulation structure is manufactured.

[0040] The principle that this manufacturing method can withstand high temperatures on the chip surface lies in that the prepared fiber-reinforced inorganic cementitious composite material can withstand higher chip surface temperatures. Attached Figure 5 is the thermal analysis curve of this inorganic cementitious material. It can be seen that before 255°C, there is basically no heat absorption, heat release, or mass loss in this material, and the composition is stable, making up for the defect that traditional organic materials are not heat-resistant; the integrally formed nano-reinforced epoxy resin reinforced shell can solve the airtightness problem of the power module, and the integrally encapsulated shell is used to replace the traditional split-type encapsulation shell. At the same time, nano-aluminum oxide is also used to improve the strength of the epoxy resin shell, providing higher impact resistance for the module and reducing the risk of damage to the module caused by external impacts.

[0041] The parameter comparison results of Example 1 and Comparative Examples 1 to 4 are as follows: Table 1 Parameter comparison of Example 1 and Comparative Examples 1 to 4

[0042] Compared with Comparative Examples 1 to 4, the operating temperature of Example 1 is higher than that of the organic encapsulation materials in the comparative examples; at the same time, compared with Comparative Examples 1 to 4, Example 1 uses a double-layer encapsulation structure with an inner organic and an outer inorganic layer to replace the single-layer encapsulation structure of the traditional encapsulation material.

[0043] Although the present invention has been described with reference to exemplary embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be broadly construed within the spirit and scope defined by the appended claims. Therefore, all changes and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A manufacturing method of a power module with a double-layer encapsulation structure, characterized in that, The main structural components of the prepared power module with a double-layer encapsulation structure include: a base plate, a nano-enhanced organic composite outer encapsulation layer, a copper-clad ceramic substrate, a chip, metal terminals, an electrical interconnection structure, and a fiber-reinforced inorganic composite inner encapsulation layer. The manufacturing steps include: S01, Chip slicing and mounting: After the whole wafer is cut, single chips are obtained. The surface of the copper-clad ceramic substrate is cleaned, and the chips are soldered to the designed positions on the surface of the copper-clad ceramic substrate through silver sintering or copper sintering process; S02, Interconnection bonding: Use a bonder to construct an electrical interconnection structure on the surface of the copper-clad ceramic substrate and the surface of the chip; S03, Welding of copper-clad ceramic substrate: The copper-clad ceramic substrate is welded to the designed position on the surface of the base plate through a vacuum reflow soldering process; S04, Fixing terminals: Use ultrasonic welding to weld the metal terminals to the designed positions; S05, Secondary interconnection bonding: Use a bonder to construct an electrical interconnection structure on the terminals and the surface of the copper-clad ceramic substrate; S06, Preparation of inorganic cementitious material powder: Alumina powder, calcium hydroxide powder, and water are mixed evenly, pressed into blocks, and heated to 1280 - 1350 °C at a heating rate of 1 - 10 °C per minute. After sintering treatment at 1280 - 1350 °C for 30 - 120 minutes, the sintered product is taken out and ball-milled into powder to make inorganic cementitious material powder; S07, Preparation of inorganic cementitious composite: Water and fiber materials are mixed, mechanically dispersed, and then mixed with inorganic cementitious material powder and a retarder. After stirring, vibration and defoaming treatment are carried out to make an inorganic cementitious composite slurry; S08, Encapsulation of inorganic cementitious composite: Assemble the inner encapsulation layer mold with the module manufactured in step S05, and pour the inorganic cementitious material slurry prepared in step S07 into the module under a vacuum degree of -0.08 to -0.09 MPa; S09, Primary heating of inorganic cementitious composite: Heat the encapsulated module at a humidity of 35% - 90% to cure the inorganic cementitious composite; S10, Secondary heating of inorganic cementitious composite: Heat the module treated in step S09 under a vacuum degree of -0.09 to -0.097 MPa to evaporate the free water in the inorganic cementitious composite; S11, Preparation of organic composite: Mix nano-filler powder with a resin mixture. The resin mixture refers to a mixture of a resin matrix, a curing agent, and a surfactant. After mixing the filler powder with the resin mixture, a fluid organic composite slurry is obtained through mechanical stirring, and vacuum defoaming treatment is carried out; S12, Encapsulation of organic composite: Remove the inner encapsulation layer mold described in S08 and replace it with an outer encapsulation layer mold. Pour the organic composite slurry prepared in step S11 into the module treated in S10 under a vacuum degree of -0.08 to -0.09 MPa; S13, Curing of organic composite: Heat and cure the power module encapsulated in step S12, and remove the outer encapsulation layer mold described in S12 after curing to obtain a power module with a double-layer encapsulation structure.

2. The manufacturing method according to claim 1, characterized in that, The raw materials of the preparation method of the inorganic gelling material powder in step S06 are calculated by weight: 50 to 100 parts of aluminum oxide powder, 110 to 260 parts of calcium hydroxide powder, and 10 to 50 parts of water; the obtained inorganic gelling material powder contains tricalcium aluminate.

3. The manufacturing method according to claim 1, wherein In the step S06, the particle size of the aluminum oxide powder is 5 to 50 microns; the particle size of the calcium hydroxide powder is 20 to 50 microns; and the particle size of the inorganic gelling material powder is 0.5 to 30 microns.

4. The manufacturing method according to claim 1, characterized in that, The preparation method of the inorganic gelled composite material slurry in step S07 comprises the following raw materials, in parts by mass: 6 to 10 parts of water, 0.02 to 0.05 parts of fiber, 0 to 0.2 parts of retarder, and 15 to 30 parts of inorganic gelled material powder; the fiber is one or more of glass fiber, basalt fiber, polyimide fiber, and alumina fiber; the fiber has a diameter of 5 to 50 microns and a length of 0.1 to 5 millimeters.

5. The manufacturing method according to claim 1, characterized in that, In the one-time heating process in step S09, the temperature is maintained at 50° C. to 85° C. for 120 to 1440 minutes.

6. The manufacturing method according to claim 1, characterized in that, In the secondary heating process in step S10, the temperature is maintained at 80-105° C. for 120-1440 minutes. The inorganic gelling material after secondary heating includes tricalcium aluminate hexahydrate, fiber, and tricalcium aluminate.

7. The manufacturing method according to claim 1, characterized in that The raw materials of the organic composite material slurry in step S11 are calculated by mass fraction as follows: 80 to 120 parts of resin matrix, 20 to 50 parts of curing agent, 0.5 to 2 parts of surfactant, 0.1 to 2 parts of accelerator, and 2.5 to 10 parts of nano filler powder; the nano filler powder is one or more of nano zirconium oxide powder, nano silicon dioxide powder, nano aluminum nitride powder, nano alumina powder, and nano boron nitride powder; the particle size of the nano filler powder is 10 to 50 nanometers, and the morphology is one or more of spherical, angular, elliptical, flaky, and rod-shaped; the resin matrix is epoxy resin.

8. A power module, characterized in that, It has a double-layer packaging structure, the inner packaging layer is a fiber-reinforced inorganic composite packaging layer, which can directly withstand a chip junction temperature higher than 240°C; the outer packaging layer is a nano-reinforced organic composite packaging layer, which has the characteristic of high strength; the power module is prepared by the method described in any one of claims 1 to 7.

Images