Method for manufacturing a power module with a double-layer packaging structure

Abstract

The present invention discloses a method for manufacturing a power module with a double-layer packaging structure, which belongs to the field of semiconductor power modules. The invention uses an aluminate inorganic gelled composite material as an inner packaging layer. The material can withstand chip junction temperatures higher than 240°C, solving the problem that traditional packaging materials are not resistant to high temperatures, and uses fiber materials to reinforce the inorganic gelled material; nano-reinforced organic composite materials are used to encapsulate and solidify the fiber-reinforced inorganic composite inner packaging layer into an integrated molded shell, solving the airtightness problem of the power module. At the same time, the integrated nano-reinforced organic composite outer packaging layer replaces the traditional split plastic shell, making the power module impact-resistant and high-strength. The method provided by the present invention can manufacture a power module with a double-layer packaging structure. The power module manufactured by the method provided by the present invention uses a double-layer packaging structure to replace traditional packaging materials and plastic shells, and has the characteristics of high strength, impact resistance, and suitability for high-junction temperature power chips.

Description

Technical Field

[0001] The 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 recent development of power electronics systems, the performance of traditional silicon-based semiconductors has been gradually exhausted. Driven by various challenges and practical needs, the rise of third-generation semiconductors has become unstoppable. Among third-generation semiconductors, silicon carbide has found widespread application in many fields due to its high breakdown field strength, high temperature resistance, and high operating frequency. In the power module field, silicon carbide MOSFET power modules have begun to partially replace traditional silicon-based IGBT modules. However, the higher power density achieved by silicon carbide chips poses a severe challenge to packaging materials. The unsuitability of existing packaging solutions has become a bottleneck restricting the progress of third-generation semiconductor devices.

[0003] Traditional potting materials for power modules usually use silicone and epoxy resin. However, as organic substances, they all have inherent defects: they are not resistant to high temperatures, and usually require modification to increase the temperature tolerance of organic potting materials. Most traditional organic potting materials on the market usually have an operating temperature below 200°C, which makes it 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 the maximum temperature can even reach 250°C. Therefore, finding a high-temperature resistant packaging material is an important part of developing higher-performance power modules. To this end, some relevant industry researchers have turned their attention to the field of inorganic materials.

[0004] The present invention adopts an inorganic-organic double-layer packaging structure, encapsulating the chip surface with a fiber-reinforced inorganic gelled composite material. During use, it can withstand chip junction temperatures exceeding 240°C. At the same time, the fiber material and inorganic gelled material are composited to prevent the encapsulation layer from cracking. The present invention encapsulates a layer of organic composite material on the surface of the inorganic gelled material and solidifies it into an encapsulation shell, solving the airtightness problem of the power module. The present invention uses an integrated encapsulated molded shell to replace the traditional split encapsulation shell, which has the characteristics of high strength and impact resistance. In addition, the present invention adds nanofillers to the organic material to strengthen the organic material, thereby improving the power module's ability to resist external physical impact 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 method for manufacturing a power module with a double-layer packaging structure, so as to manufacture a power module that can carry higher power density and withstand 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 packaging structure, characterized in that the prepared power module with a double-layer packaging structure mainly comprises: a base plate, a nano-reinforced organic composite outer packaging layer, a copper-clad ceramic substrate, a chip, metal terminals, an electrical interconnection structure, and a fiber-reinforced inorganic composite inner packaging layer. The manufacturing steps include:

[0007] S01, chip slicing and placement: After the whole wafer is cut, a single chip is obtained. The surface of the copper-clad ceramic substrate is cleaned and the chip is soldered to the designed position on the surface of the copper-clad ceramic substrate through silver sintering or copper sintering process;

[0008] S02, interconnect bonding: Use a bonding machine to build an electrical interconnect structure on the surface of the copper-clad ceramic substrate and the chip surface;

[0009] S03, copper-clad ceramic substrate welding: solder the copper-clad ceramic substrate to the designed position on the surface of the base plate through vacuum reflow process;

[0010] S04, fixed terminal: use ultrasonic welding to weld the metal terminal to the designed position;

[0011] S05, secondary interconnect bonding: Use a bonding machine to build an electrical interconnect structure between the terminal and the surface of the copper-clad ceramic substrate;

[0012] S06, preparation of inorganic gelling material powder: alumina powder, calcium hydroxide powder, and water are uniformly mixed, pressed into blocks, and heated to 1280-1350° C. at a heating rate of 1-10° C. / min. After sintering at 1280-1350° C. for 30-120 minutes, the sintered product is removed and ball-milled into powder to prepare inorganic gelling material powder;

[0013] S07, preparing an inorganic gelled composite material: mixing water and a fiber material, mechanically dispersing the mixture, mixing the mixture with an inorganic gelled material powder and a retarder, stirring the mixture, and vibrating and removing bubbles to prepare an inorganic gelled composite material slurry;

[0014] S08, potting of inorganic gelling composite material: assembling the inner packaging layer mold and the module manufactured in step S05, and pouring the inorganic gelling material slurry prepared in step S07 into the module under a vacuum degree of -0.08 to -0.09 MPa;

[0015] S09, primary heating of the inorganic gelled composite material: heating the potted module at a humidity of 35% to 90% to solidify the inorganic gelled composite material;

[0016] S10, secondary heating of the inorganic gelled composite material: heating the module after the treatment in step S09 under a vacuum degree of -0.09 to -0.097 MPa to evaporate free water in the inorganic gelled composite material;

[0017] S11, preparation of organic composite material: mixing nano filler powder with a resin mixture, wherein the resin mixture is a mixture of a resin matrix, a curing agent, and a surfactant, mechanically stirring the filler powder and the resin mixture to obtain a fluid organic composite material slurry, and performing a vacuum degassing treatment;

[0018] S12, potting of organic composite material: the inner encapsulation layer mold described in S08 is removed and replaced with an outer encapsulation 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;

[0019] S13, curing the organic composite material: heating and curing the power module encapsulated in step S12, and removing the outer packaging layer mold in step S12 after curing to obtain a power module with a double-layer packaging structure;

[0020] Furthermore, it is characterized in that the raw materials for preparing 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 is composed of tricalcium aluminate.

[0021] 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.

[0022] Furthermore, it is characterized in that the raw materials of the preparation method of the inorganic gelled 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 gelled 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.

[0023] 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.

[0024] 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.

[0025] Furthermore, 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 nanofiller powder; the nanofiller 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 nanofiller 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.

[0026] The power module has the characteristics of high strength and high junction temperature resistance. Compared with the existing technology, it has the following advantages:

[0027] 1. The present invention uses an aluminate inorganic gelled composite material as the inner packaging layer. This material can withstand chip junction temperatures above 240°C, solving the problem of traditional packaging materials being unable to withstand high temperatures. The chip performance is no longer constrained by the packaging material, and fiber materials are used to reinforce the inorganic gelled material to prevent cracking of the packaging layer.

[0028] 2. The present invention uses a nano-reinforced organic composite material integrally formed shell outside the fiber-reinforced inorganic composite inner packaging layer, which solves the airtightness problem of the power module. At the same time, the nano-reinforced organic composite outer packaging layer replaces the traditional split plastic shell, making the power module impact-resistant and high-strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Attachment Figure 1 The figure shows a schematic diagram of the manufacturing process of the power module with a double-layer packaging structure according to the present invention.

[0030] Attachment Figure 2 The figure shows a schematic diagram of the power module structure with a double-layer packaging structure according to the present invention, wherein (a) is a schematic diagram of the appearance of the power module, (b) is an exploded diagram of the internal structure of the power module, and (c) is a schematic diagram of the cross-sectional structure of the power module.

[0031] Attachment Figure 3 Figure 2 is a schematic diagram of the potting process of the fiber-reinforced inorganic gelled composite material according to the present invention, wherein (a) is a schematic diagram of the inner packaging layer mold structure, (b) is a schematic diagram of the assembly structure of the inner packaging layer mold and the module semi-finished product, (c) is a schematic diagram of the potting and curing molding process of the fiber-reinforced inorganic gelled composite material, and (d) is a schematic diagram of the semi-finished power module obtained by removing the inner packaging layer mold.

[0032] Attachment Figure 4Figure 2 is a schematic diagram of the potting process of the nano-enhanced organic composite material according to the present invention, wherein (a) is a schematic diagram of the outer packaging layer mold structure, (b) is a schematic diagram of the assembly structure of the outer packaging layer mold and the module semi-finished product, (c) is a schematic diagram of the potting and curing molding process of the nano-enhanced organic composite material, and (d) is a schematic diagram of the power module with a double-layer packaging structure obtained by removing the outer packaging layer mold.

[0033] Attachment Figure 5 Shown is a thermal analysis curve of the inorganic gelled composite material of the present invention.

[0034] Attachment Figure 6 Shown are the XRD comparison charts of the inorganic gelling material prepared in specific example 1 and the inorganic gelling material powder and the standard card, wherein (a) is the XRD comparison chart of the inorganic gelling material powder and the tricalcium aluminate standard card, and (b) is the XRD comparison chart of the inorganic gelling material and the tricalcium aluminate hexahydrate and the tricalcium aluminate standard card. DETAILED DESCRIPTION

[0035] Specific embodiments of the present invention will be described in detail below. It should be noted that the embodiments described herein are for illustration only and are not intended to limit the present invention. In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that these specific details are not necessarily required to practice the present invention. In other examples, well-known structures, circuits, materials, or methods are not specifically described to avoid obscuring the present invention.

[0036] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "in one embodiment," "in an embodiment," "an example," or "an example" appearing in various places throughout the specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combinations and / or subcombinations in one or more embodiments or examples. The present invention is described in detail below with reference to the accompanying drawings.

[0037] In the following description of the technical solution of the present invention in conjunction with the accompanying drawings, the sizes, proportions and positional relationships of the elements are only exemplary, and the connection methods between the illustrated elements are only for illustration and are not intended to limit the present invention.

[0038] Example

[0039] The example illustrates the application of the power module manufacturing method with a double-layer packaging structure in the manufacture of silicon carbide MOSFET power modules.

[0040] Refer to the attached Figure 2 The silicon carbide MOSFET power module has the following main structures: base plate 101, active metal brazing substrate 102, chip 103, metal lead 104, fiber reinforced inorganic composite inner packaging layer 105, nano-reinforced organic composite outer packaging layer 106, metal terminal 107; refer to the attached Figure 3 In (a), the inner package mold has the following main structures: inner package mold section A 201, inner package mold section B 202, terminal through hole 203, bottom plate groove 204; Figure 4 In (a), the outer packaging mold has the following main structures: outer packaging layer mold section A 301 , outer packaging layer mold section B 302 , and terminal through-holes 303 .

[0041] Refer to the attached Figure 1 A series of steps from S01 chip slicing and mounting to S13 organic composite material curing are performed to obtain a power module with a double-layer packaging structure.

[0042] S01, chip slicing and mounting, first clean the surface of the active metal brazing substrate 102, remove oxides and contaminants, and evenly coat the sintered copper paste on the designed area of the active metal brazing substrate by screen printing; cut the entire wafer to obtain the chip 103, and use a chip mounter to accurately mount the chip 103 on the copper paste coating area on the active metal brazing substrate 102; treat the active metal brazing substrate 102 with the chip mounted at 150°C for 10 minutes, dry the copper paste, remove the organic solvent, and form a preliminary copper particle accumulation layer. During the process, nitrogen is introduced as a protective atmosphere to prevent oxidation of the copper particles; then high-temperature sintering is performed in a hot pressing sintering furnace: the working temperature is set to 275°C, the working time is 5 minutes, the working pressure is 25MPa, and nitrogen is introduced as a protective atmosphere to achieve densification and sintering of the copper particles.

[0043] S02, interconnect bonding, using a bonding machine to complete the bonding of the metal wires 104 on the surface of the chip 103 and the active metal brazing substrate 102 using an ultrasonic wire bonding process, and using ultrasonic waves to clean the metal pins.

[0044] S03, active metal brazing substrate welding, clean the surface of the base plate 101, remove oxides and contaminants, and attach the active metal brazing substrate 102 and the brazing sheet that have completed the bonding work to the surface of the base plate 101. Then, send them into a vacuum reflow furnace, introduce nitrogen as a protective atmosphere, and gradually increase the temperature to 245°C; start vacuuming at 245°C, maintain the vacuum degree at -0.0995MPa for 60 seconds, and then return to normal temperature and pressure.

[0045] S04, fix the terminal and weld the metal terminal 107 to the designed position using an ultrasonic welding gun.

[0046] S05, secondary interconnection bonding, using a bonding machine to adopt an ultrasonic wire bonding process on the surface of the active metal brazing substrate 102 to complete the electrical interconnection between the metal terminal 107 and the active metal brazing substrate 102.

[0047] S06, prepare inorganic gelling material powder, alumina powder with a particle size of 45 microns, calcium hydroxide powder with a particle size of 30 microns, and water in a mass ratio of 10:20:8, stir and evenly press into blocks, place in a muffle furnace and heat at a heating rate of 3°C / min to 1350°C and keep warm for 30 minutes, take out the sintered product, crush it, and place it in a ball mill for ball milling to obtain inorganic gelling material powder with an average particle size of 5 microns, and Figure 6 From (a) in the figure, it can be seen that the prepared powder component is tricalcium aluminate.

[0048] S07: Prepare an inorganic gelling material by mixing polyimide fibers (20 μm in diameter and 1 mm in length) with water at a mass ratio of 1:20 and mechanically dispersing for 10 minutes to obtain a polyimide fiber aqueous dispersion. Then, mix tricalcium aluminate powder, the polyimide fiber aqueous dispersion, and borax at a mass ratio of 20:9:0.3 and vibrate to remove bubbles.

[0049] S08, Inorganic gelled composite material potting, the specific process is as shown in the attached Figure 3 As shown, the inner encapsulation layer mold section A 201, the inner encapsulation layer mold section B 202 and the modules manufactured in steps S01 to S05 are assembled, and the inorganic gelling material slurry prepared in S07 is filled into the modules manufactured in steps S01 to S05 using a vacuum glue filling machine at a vacuum degree of -0.085 MPa and a glue filling speed of 100 ml / min.

[0050] S09, primary heating of the inorganic gelled composite material, heating the module encapsulated in S07 at 60°C and 50% humidity for 12 hours.

[0051] S10, secondary heating of the inorganic gelled composite material, heating the module treated in S08 at 95°C and -0.095 MPa vacuum for 24 hours, and obtaining a fiber reinforced inorganic composite inner packaging layer 105 after curing. Figure 6 From (b) in FIG. 1 , it can be seen that the main component of the inorganic gelled composite material after secondary heating is tricalcium aluminate hexahydrate.

[0052] S11, preparation of composite materials: aromatic epoxy resin with a glass transition temperature greater than 185°C, curing agent, surfactant, and accelerator are mixed in a ratio of 100:30:1:1 and mechanically stirred at room temperature for 5 minutes. Then, spherical nano-alumina powder with a particle size of 30 nm is mixed with the resin mixture in a mass ratio of 1:25, and vacuum degassing treatment is performed.

[0053] S12, potting of organic composite materials, the specific process is as shown in the attached Figure 4 As shown, after the inner encapsulation layer mold section A 201 and the inner encapsulation layer mold section B 202 described in S08 are removed and the outer encapsulation layer mold section A 301 and the outer encapsulation layer mold section B 302 are assembled with the module, a vacuum glue filling machine is used at a vacuum degree of -0.085 MPa and a glue filling speed of 35 ml / min to fill the organic composite material slurry prepared in S11 into the module encapsulated by the inorganic material treated by S08 to S10.

[0054] S13, curing of the organic composite material. After pre-curing the module after potting in step S12 at 95°C for 2 hours, it is cured at 160°C for 2 hours to cross-link and cure the resin to obtain a nano-reinforced organic composite outer packaging layer 106. After the curing is completed, the outer packaging layer mold section A 301 and the outer packaging layer mold section B 302 described in S12 are removed to obtain a power module with a double-layer packaging structure.

[0055] The principle of this manufacturing method being able to withstand high temperatures on the chip surface is that the prepared fiber-reinforced inorganic gelled composite material can withstand higher chip surface temperatures. Figure 5 This is the thermal analysis curve of the inorganic gelling material. It can be seen that the material basically does not absorb or release heat or lose mass before 255°C. The composition is stable, which makes up for the defect of traditional organic materials not being resistant to high temperatures. The one-piece nano-reinforced epoxy resin reinforced shell can solve the airtightness problem of the power module, and the one-piece potting molded shell replaces the traditional split packaging shell. At the same time, nano-alumina is used to improve the strength of the epoxy resin shell, providing the module with higher impact resistance and reducing the risk of damage to the module by external impact.

[0056] The results of parameter comparison between Example 1 and Comparative Examples 1 to 4 are as follows:

[0057] Table 1 Parameter comparison of Example 1 and Comparative Examples 1 to 4

[0058]

[0059] Compared with Comparative Examples 1 to 4, the operating temperature of Example 1 is higher than that of the organic potting materials in the comparative examples; at the same time, compared with Comparative Examples 1 to 4, Example 1 uses a double-layer packaging structure of inner organic layer and outer inorganic layer to replace the single-layer packaging structure of the traditional potting material.

[0060] While the present invention has been described with reference to exemplary embodiments, it should be understood that the terms used are descriptive and illustrative 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-described embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope of the appended claims. All changes and modifications that fall within the scope of the claims or their equivalents are intended to be covered by the appended claims.

Claims

1. A method for manufacturing a power module with a double-layer packaging structure, characterized in that: The main components of the prepared power module with a double-layer packaging structure include: a base plate, a nano-enhanced organic composite outer packaging layer, a copper-clad ceramic substrate, a chip, metal terminals, an electrical interconnection structure, and a fiber-reinforced inorganic composite inner packaging layer. The manufacturing steps include: S01, chip slicing and placement: After the whole wafer is cut, a single chip is obtained. The surface of the copper-clad ceramic substrate is cleaned and the chip is soldered to the designed position on the surface of the copper-clad ceramic substrate through silver sintering or copper sintering process; S02, interconnect bonding: Use a bonding machine to build an electrical interconnect structure on the surface of the copper-clad ceramic substrate and the chip surface; S03, copper-clad ceramic substrate welding: solder the copper-clad ceramic substrate to the designed position on the surface of the base plate through vacuum reflow process; S04, fixed terminal: use ultrasonic welding to weld the metal terminal to the designed position; S05, secondary interconnect bonding: Use a bonding machine to build an electrical interconnect structure between the terminal and the surface of the copper-clad ceramic substrate; S06, preparation of inorganic gelling material powder: alumina powder, calcium hydroxide powder, and water are uniformly mixed, pressed into blocks, and heated to 1280-1350° C. at a heating rate of 1-10° C. / min. After sintering at 1280-1350° C. for 30-120 minutes, the sintered product is removed and ball-milled into powder to prepare inorganic gelling material powder; S07, preparing an inorganic gelled composite material: mixing water and a fiber material, mechanically dispersing the mixture, mixing the mixture with an inorganic gelled material powder and a retarder, stirring the mixture, and vibrating and removing bubbles to prepare an inorganic gelled composite material slurry; S08, potting of inorganic gelling composite material: assembling the inner packaging layer mold and the module manufactured in step S05, and pouring the inorganic gelling material slurry prepared in step S07 into the module under a vacuum degree of -0.08 to -0.09 MPa; S09, primary heating of the inorganic gelled composite material: heating the potted module at a humidity of 35% to 90% to solidify the inorganic gelled composite material; S10, secondary heating of the inorganic gelled composite material: heating the module after the treatment in step S09 under a vacuum degree of -0.09 to -0.097 MPa to evaporate free water in the inorganic gelled composite material; S11, preparation of organic composite material: mixing nano filler powder with a resin mixture, wherein the resin mixture is a mixture of a resin matrix, a curing agent, and a surfactant, mechanically stirring the filler powder and the resin mixture to obtain a fluid organic composite material slurry, and performing a vacuum degassing treatment; S12, potting of organic composite material: the inner encapsulation layer mold described in S08 is removed and replaced with an outer encapsulation 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 after potting in step S12, and removing the outer packaging layer mold in step S12 after curing to obtain a power module with a double-layer packaging structure.

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

3. The manufacturing method according to claim 1, 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.

4. The manufacturing method according to claim 1, characterized in that The preparation method of the inorganic gelled composite material slurry in step S07 has 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 mm.

5. The manufacturing method according to claim 1, characterized in that In the first 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 comprises 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 characteristics of high strength; the power module is prepared by the method described in any one of claims 1 to 7.

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