BGA packaging process of memory product

Abstract

The application discloses a BGA packaging process of a memory product and belongs to the field of semiconductor packaging. 3+ The BGA packaging process comprises the following steps: S1, preparing a bottom filling adhesive, wherein the bottom filling adhesive comprises the following components: a ternary epoxy resin blending system, modified nano-ZnO, boron nitride nanotubes, a curing agent and other additives, wherein the modified nano-ZnO is ZnO@PDA-Fe 3+ -SiC composite structure; S2, preheating the substrate, and the preheating temperature is 40-60 DEG C; S3, continuously dispensing along the single side of the chip by using a dispensing machine, and utilizing the capillary effect to make the bottom filling adhesive naturally diffuse and fill into the gap between the chip and the substrate; S4, after the bottom filling adhesive naturally fills the gap, heating and curing are carried out, and the bottom filling between the chip and the substrate is completed. In the application, the modified nano-zinc oxide can realize high addition amount, high dispersibility, low water absorption and high mechanical property of the bottom filling adhesive under the condition of high addition amount.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor packaging and relates to a BGA packaging process for memory products. Background Technology

[0002] In flip-chip electronic packaging, adding underfill to the chip and substrate can improve reliability and reduce interfacial stress caused by the difference in thermal expansion coefficients between the solder joint and the substrate. However, current methods of using underfill have the following problems: Currently, to improve the performance of epoxy resin underfill, nanofillers are usually added to reduce the water absorption of the underfill and improve its shear strength, temperature resistance, and other properties. Nanofillers are often modified by dispersing nano-zinc oxide using silane coupling agents. A 2019 paper, "The Influence of Nanofillers on the Performance of Epoxy Resin-Based Underfill," specifically analyzed this, showing that the maximum addition amount of nano-zinc oxide in underfill can only reach 3% while maintaining low water absorption. Adding more than 3% causes nano-zinc oxide to agglomerate, which actually increases water absorption. However, at 3% addition, the shear strength and other properties of the underfill cannot reach their maximum. Therefore, the dispersion limitation of silane coupling agent-modified nano-zinc oxide is currently a problem. Summary of the Invention

[0003] The purpose of this invention is to provide a BGA packaging process for memory products, which solves the problem of limited dispersion of nano-zinc oxide modified with alkyl coupling agents in the current process of modifying epoxy resin-based bottom filler with nanofillers.

[0004] The technical solution adopted in this invention is as follows:

[0005] A BGA packaging process for a memory product includes an underfill process between the chip and the substrate, wherein the underfill process includes the following steps:

[0006] S1. Prepare the underfill adhesive, wherein the underfill adhesive comprises the following components: a ternary epoxy resin blend system, modified nano-ZnO, boron nitride nanotubes, a curing agent, and other additives, wherein the modified nano-ZnO is ZnO@PDA-Fe 3+ -SiC composite structure;

[0007] S2. Preheat the substrate to a temperature of 40-60°C;

[0008] S3. Use a dispensing machine to continuously dispense adhesive along one side of the chip, utilizing the capillary effect to allow the bottom filler adhesive to naturally diffuse and fill the gap between the chip and the substrate.

[0009] S4. After the bottom filler glue naturally fills the gaps, it is heated and cured to complete the bottom filling between the chip and the substrate.

[0010] Furthermore, the method for preparing the bottom filler in step S1 is as follows:

[0011] S1.1 Preparation of modified nano-ZnO: ZnO was dispersed in Tris buffer solution at pH 8.5, dopamine was added, and the mixture was shaken at 25°C for 6 hours. After centrifugation, washing, and drying, ZnO@PDA particles were obtained. The ZnO@PDA particles were then immersed in FeCl3 ethanol solution, stirred at 60°C for 2 hours, and washed and dried to obtain ZnO@PDA-FeCl3. 3+ Composite structure; ZnO@PDA-Fe 3+ The mixture was placed in a tube furnace and purged with a SiH4 and CH4 gas mixture. After reacting at 600°C for 30 min, it was treated under an ammonia atmosphere for 30 min to obtain ZnO@PDA-Fe. 3+ -SiC composite structure, the ZnO@PDA-Fe 3+ -The SiC composite structure is modified nano-ZnO;

[0012] S1.2 After heating the ternary epoxy resin blend system to 80-90℃, add modified nano-ZnO and boron nitride nanotubes at a constant temperature, and sonicate at 40kHz for 1-1.5 hours to obtain the first intermediate.

[0013] S1.3 At 80℃, a 1T magnetic field was applied to the first intermediate for 5 minutes, and then the magnetic field strength was linearly reduced to 0.5T and maintained for 12 minutes to perform the first magnetic field induction, thereby obtaining the second intermediate;

[0014] S1.4 Add curing agent and other additives to the second intermediate, stir and mix evenly, then apply a 0.3T weak magnetic field at room temperature for 2 minutes to perform a second magnetic field induction, vacuum degassing, and obtain the bottom filler adhesive.

[0015] Furthermore, the amount of modified nano-ZnO added is 7-8% of the mass of the ternary epoxy resin blend system, the mass ratio of boron nitride nanotubes to modified nano-ZnO is 1.8-2:1, and the amount of curing agent added is 20-25% of the mass of the ternary epoxy resin blend system.

[0016] Furthermore, the mass ratio of ZnO to dopamine is 10:1.

[0017] Furthermore, the volume ratio of SiH to CH in the SiH4 and CH4 mixed gas is 1:4.

[0018] Furthermore, the other additives include aluminum borate whiskers and fumed silica. The amount of aluminum borate whiskers added is 3-5% of the mass of the ternary epoxy resin blend system, and the amount of fumed silica added is 0.3-0.5% of the mass of the ternary epoxy resin blend system.

[0019] Furthermore, the ternary epoxy resin blend system comprises the following components: polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin, wherein the mass ratio of polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin is 1:3-5:1.

[0020] Furthermore, the curing agent includes QNP1 type low-temperature latent epoxy resin curing agent and acid anhydride curing agent, and the mass ratio of QNP1 type low-temperature latent epoxy resin curing agent to acid anhydride curing agent is 2:1.

[0021] Furthermore, the curing method in step S4 is as follows: first heat to 80-85℃, hold the temperature for 5 minutes, then continue to heat to 120℃-130℃ and hold for another 8-10 minutes.

[0022] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0023] 1. This invention improves the bottom filling method of a BGA packaging process for memory products by employing a novel modified nano-zinc oxide combined with magnetic field induction technology. This replaces the existing technique of modifying nano-zinc oxide with silane coupling agents to improve its dispersibility in an epoxy resin matrix. The modified nano-zinc oxide of this invention has a four-layer composite structure, in which the hydroxyl groups on the ZnO surface are bonded to the catechol groups of dopamine via hydrogen bonds. The dopamine layer inhibits ZnO aggregation through steric hindrance, achieving the first-step dispersion; Fe 3+ The phenolic hydroxyl groups of PDA form coordination bonds, giving the particle surface a positive charge, which is then further dispersed through electrostatic repulsion; in magnetic field induction, Fe... 3+ The paramagnetism of the modified ZnO causes it to align along the magnetic field lines in a magnetic field, reducing the probability of agglomeration. Furthermore, the magnetic properties of the boron nitride nanotubes cause them to align along the magnetic field direction, intertwining with ZnO to form a three-dimensional network, thus anchoring the nanoparticles and further improving dispersibility. The chemical inertness of SiC reduces surface energy and decreases moisture adsorption sites. In this invention, the modified nano-zinc oxide can achieve high addition amounts and high dispersibility in the bottom filler, while also achieving low water absorption and high mechanical properties even at high addition amounts.

[0024] 2. The SiC in the modified nano zinc oxide of this invention is obtained by deposition. On the one hand, the SiC layer is thin and not dense, which reduces the water absorption rate of nano zinc oxide without affecting the electrostatic repulsion dispersion; the outer SiC layer acts as a physical barrier to prevent water molecules from penetrating into the interior; the PDA layer acts as a chemical barrier to further hinder water diffusion through hydrophobic structure and interfacial crosslinking.

[0025] 3. This invention uses a ternary epoxy resin blend system instead of the existing single-component epoxy resin because the addition of high amounts of nanofillers to traditional single-component epoxy resins can disrupt the continuity of the resin molecular chains, weakening its ability to reduce interfacial stress caused by the difference in thermal expansion coefficients between the welding point and the substrate. In order to compensate for this problem during the actual research and development process, this invention uses a mixture of polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin instead of a single epoxy resin. Through flexible polyurethane bridging, bisphenol F wetting, and high crosslinking of phenolic resin, the disrupting effect of high filler content is offset.

[0026] 4. Compared with single epoxy resin, the ternary epoxy resin blend system in this invention provides a gradient distribution of the coefficient of thermal expansion. Compared with the fixed coefficient of thermal expansion of single epoxy resin, it reduces the degree of thermal expansion mismatch, realizes a gradual CTE transition, and avoids abrupt stress. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort, wherein:

[0028] Figure 1 This is a block diagram of the underfill process in the BGA packaging process of a memory product. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0031] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0033] Example 1

[0034] like Figure 1 As shown, a preferred embodiment of the present invention provides a BGA packaging process for a memory product, including an underfill process between the chip and the substrate, wherein the underfill process includes the following steps:

[0035] S1. Prepare the underfill adhesive, wherein the underfill adhesive comprises the following components: a ternary epoxy resin blend system, modified nano-ZnO, boron nitride nanotubes, a curing agent, and other additives, wherein the modified nano-ZnO is ZnO@PDA-Fe 3+ -SiC composite structure;

[0036] S2. Preheat the substrate to a temperature of 40-60°C;

[0037] S3. Use a dispensing machine to continuously dispense adhesive along one side of the chip, utilizing the capillary effect to allow the bottom filler adhesive to naturally diffuse and fill the gap between the chip and the substrate.

[0038] S4. After the bottom filler glue naturally fills the gaps, it is heated and cured to complete the bottom filling between the chip and the substrate.

[0039] The preparation method of the bottom filler in step S1 is as follows:

[0040] S1.1 Preparation of modified nano-ZnO: ZnO was dispersed in Tris buffer solution at pH 8.5, dopamine was added, and the mixture was shaken at 25°C for 6 hours. After centrifugation, washing, and drying, ZnO@PDA particles were obtained. The ZnO@PDA particles were then immersed in FeCl3-ethanol solution, stirred at 60°C for 2 hours, and then washed and dried to obtain ZnO@PDA-FeCl3. 3+ Composite structure; ZnO@PDA-Fe 3+The mixture was placed in a tube furnace and purged with a SiH4 and CH4 gas mixture. After reacting at 600°C for 30 min, it was treated under an ammonia atmosphere for 30 min to obtain ZnO@PDA-Fe. 3+ -SiC composite structure, the ZnO@PDA-Fe 3+ -The SiC composite structure is modified nano-ZnO;

[0041] S1.2 After heating the ternary epoxy resin blend system to 80-90℃, add modified nano-ZnO and boron nitride nanotubes at a constant temperature, and sonicate at 40kHz for 1-1.5 hours to obtain the first intermediate.

[0042] S1.3 At 80℃, a 1T magnetic field was applied to the first intermediate for 5 minutes, and then the magnetic field strength was linearly reduced to 0.5T and maintained for 12 minutes to perform the first magnetic field induction, thereby obtaining the second intermediate;

[0043] S1.4 Add curing agent and other additives to the second intermediate, stir and mix evenly, apply a weak magnetic field of 0.3T at room temperature for 2 minutes, and degas under vacuum to obtain the bottom filler.

[0044] The amount of modified nano-ZnO added is 7% of the mass of the ternary epoxy resin blend system, the mass ratio of boron nitride nanotubes to modified nano-ZnO is 1.8:1, and the amount of curing agent added is 20% of the mass of the ternary epoxy resin blend system.

[0045] The mass ratio of ZnO to dopamine is 10:1.

[0046] The volume ratio of SiH to CH in the SiH4 and CH4 mixed gas is 1:4.

[0047] The other additives include aluminum borate whiskers and fumed silica. The amount of aluminum borate whiskers added is 3-5% of the mass of the ternary epoxy resin blend system, and the amount of fumed silica added is 0.3-0.5% of the mass of the ternary epoxy resin blend system.

[0048] The ternary epoxy resin blend system comprises the following components: polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin, wherein the mass ratio of polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin is 1:3:1.

[0049] The curing agent includes QNP1 type low-temperature latent epoxy resin curing agent and acid anhydride curing agent, with a mass ratio of QNP1 type low-temperature latent epoxy resin curing agent to acid anhydride curing agent of 2:1.

[0050] The curing method for step S4 is as follows: first heat to 80-85℃, hold the temperature for 5 minutes, then continue to heat to 120℃-130℃ and hold for another 8-10 minutes.

[0051] Example 2

[0052] This embodiment differs from Embodiment 1 in that: the amount of modified nano-ZnO added is 7.5% of the mass of the ternary epoxy resin blend system, the mass ratio of boron nitride nanotubes to modified nano-ZnO is 1.9:1, and the amount of curing agent added is 22.5% of the mass of the ternary epoxy resin blend system.

[0053] Example 3

[0054] This embodiment differs from Embodiment 1 in that: the amount of modified nano-ZnO added is 8% of the mass of the ternary epoxy resin blend system, the mass ratio of boron nitride nanotubes to modified nano-ZnO is 2:1, and the amount of curing agent added is 25% of the mass of the ternary epoxy resin blend system.

[0055] Example 4

[0056] This embodiment differs from Embodiment 1 in that, based on Embodiment 2, the ternary epoxy resin blend system includes the following components: polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin, with a mass ratio of 1:4:1.

[0057] Example 5

[0058] This embodiment differs from Embodiment 1 from Embodiment 2 in that the ternary epoxy resin blend system includes the following components: polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin, with a mass ratio of 1:5:1.

[0059] Comparative Example 1

[0060] This comparative example differs from Example 1 in that the underfill adhesive and its preparation method are based on the components and preparation method given in "The Influence of Nanofillers on the Performance of Epoxy Resin-Based Underfill Adhesives" by Zhang Xin, Guo Wenli, and Liang Tongxiang. The modified zinc oxide is a silane coupling agent-modified nanofiller, and the amount added is 0.3% of the epoxy resin mass. The filling process steps of the underfill adhesive are the same, only the components and preparation method of the underfill adhesive are different.

[0061] Comparative Example 2

[0062] This comparative example differs from Example 1 in that the modified nano-ZnO in the bottom filler of this comparative example does not include the outer SiC layer.

[0063] Comparative Example 3

[0064] This comparative example differs from Example 1 in that the modified nano-ZnO in the bottom filler of this comparative example does not include the intermediate Fe. 3+ layer.

[0065] Comparative Example 4

[0066] This comparative example differs from Example 1 in that the modified nano-ZnO in the bottom filler of this comparative example does not include a PDA layer. Therefore, a stable multilayer structure cannot be formed.

[0067] Comparative Example 5

[0068] This comparative example differs from Example 1 in that the modified nano-ZnO in the bottom filler of this comparative example does not include a SiC layer and Fe. 3+ layer.

[0069] Comparative Example 6

[0070] This comparative example differs from Example 1 in that the bottom filler adhesive in this comparative example does not include boron nitride nanotubes.

[0071] Comparative Example 7

[0072] This comparative example differs from Example 1 in that the preparation process of the bottom filler adhesive in this comparative example does not involve the first magnetic field induction.

[0073] Comparative Example 8

[0074] This comparative example differs from Example 1 in that the bottom filler adhesive in this comparative example is not subjected to a second magnetic field induction during its preparation process.

[0075] Comparative Example 9

[0076] This comparative example differs from Example 1 in that the preparation process of the bottom filler adhesive in this comparative example does not involve the first and second magnetic field inductions.

[0077] Comparative Example 10

[0078] This comparative example differs from Example 1 in that it uses a single bisphenol F epoxy resin instead of a ternary epoxy resin blend in the underfill adhesive. During testing, it was found that underfill adhesives prepared using a single polyurethane-modified epoxy resin or phenolic epoxy resin had poor flowability and could not achieve uniform filling, making them unsuitable for the underfilling process of this invention.

[0079] Comparative Example 11

[0080] This comparative example differs from Example 1 in that the ternary epoxy resin blend system in the underfill adhesive of this comparative example does not include bisphenol F type epoxy resin. Therefore, uniform filling cannot be achieved, and the underfilling process of this invention is not applicable.

[0081] Comparative Example 12

[0082] This comparative example differs from Example 1 in that the ternary epoxy resin blend system in the bottom filler of this comparative example does not include polyurethane-modified epoxy resin.

[0083] Comparative Example 13

[0084] This comparative example differs from Example 1 in that the ternary epoxy resin blend system in the bottom filler of this comparative example does not include phenolic epoxy resin.

[0085] Experimental Example 1

[0086] The shear strength, water absorption (water absorption rate), and heat resistance (decomposition temperature) of the underfill adhesives prepared in Examples 1-5 and Comparative Examples 1-13 were tested. The test methods were based on the test methods given by Zhang Xin, Guo Wenli, and Liang Tongxiang in "The Influence of Nanofillers on the Performance of Epoxy Resin-Based Underfill Adhesives". The results are shown in Table 1.

[0087] Table 1 Performance testing of the bottom filler

[0088]

[0089]

[0090] Compared with the prior art, the present invention can improve shear strength and heat resistance while maintaining low water absorption, even with a higher than the optimal addition amount of existing fillers.

[0091] Experimental Example 2

[0092] The curing time at 130°C and the viscosity at 25°C + 55% relative humidity were tested in Examples 1-5. The test results are shown in Table 2.

[0093] Table 2 Performance of the underfill adhesive in Examples 1-5

[0094] Example 1 ≤15 minutes 800-1000 mPa.s Example 2 ≤15 minutes 800-1000 mPa.s Example 3 ≤15 minutes 800-1000 mPa.s Example 4 ≤15 minutes 800-1000 mPa.s Example 5 ≤15 minutes 800-1000 mPa.s

[0095] Experimental Example 3

[0096] Stress failure verification was performed by conducting temperature cycling tests from 0°C to 125°C on CBGA devices packaged using the bottom fill process of Examples 1-5 and Comparative Examples 10-13 to detect the number of cycles required to prevent stress failure. The detection method was based on existing technology, and the results are shown in Table 3.

[0097] Table 3 Results of stress failure tests

[0098]

[0099] In this invention, the ternary epoxy resin blend system can effectively alleviate the situation where filler particles interrupt the continuity of resin molecular chains, thus weakening its ability to reduce interfacial stress caused by the difference in thermal expansion coefficients between the welding point and the substrate.

[0100] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A BGA packaging process for a memory product, including an underfill process between the chip and the substrate, characterized in that: The bottom filling process includes the following steps: S1. Prepare the underfill adhesive, wherein the underfill adhesive comprises the following components: a ternary epoxy resin blend system, modified nano-ZnO, boron nitride nanotubes, a curing agent, and other additives, wherein the modified nano-ZnO is ZnO@PDA-Fe 3+ -SiC composite structure; S2. Preheat the substrate to a temperature of 40-60°C; S3. Use a dispensing machine to continuously dispense adhesive along one side of the chip, utilizing the capillary effect to allow the bottom filler adhesive to naturally diffuse and fill the gap between the chip and the substrate. S4. After the bottom filler glue naturally fills the gaps, it is heated and cured to complete the bottom filling between the chip and the substrate.

2. The BGA packaging process for a memory product according to claim 1, characterized in that: The preparation method of the bottom filler in step S1 is as follows: S1.1 Preparation of modified nano-ZnO: ZnO was dispersed in Tris buffer solution at pH 8.5, dopamine was added, and the mixture was shaken at 25°C for 6 hours. After centrifugation, washing, and drying, ZnO@PDA particles were obtained. The ZnO@PDA particles were then immersed in FeCl3 ethanol solution, stirred at 60°C for 2 hours, and washed and dried to obtain ZnO@PDA-FeCl3. 3+ Composite structure; ZnO@PDA-Fe 3+ The mixture was placed in a tube furnace and purged with a SiH4 and CH4 gas mixture. After reacting at 600°C for 30 min, it was treated under an ammonia atmosphere for 30 min to obtain ZnO@PDA-Fe. 3+ -SiC composite structure, the ZnO@PDA-Fe 3+ -The SiC composite structure is modified nano-ZnO; S1.2 After heating the ternary epoxy resin blend system to 80-90℃, add modified nano-ZnO and boron nitride nanotubes at a constant temperature, and sonicate at 40kHz for 1-1.5 hours to obtain the first intermediate. S1.3 At 80℃, a 1T magnetic field was applied to the first intermediate for 5 minutes, and then the magnetic field strength was linearly reduced to 0.5T and maintained for 12 minutes to perform the first magnetic field induction, thereby obtaining the second intermediate; S1.4 Add curing agent and other additives to the second intermediate, stir and mix evenly, apply a weak magnetic field of 0.3T at room temperature for 2 minutes, and degas under vacuum to obtain the bottom filler.

3. The BGA packaging process for a memory product according to claim 2, characterized in that: The amount of modified nano-ZnO added is 7-8% of the mass of the ternary epoxy resin blend system, the mass ratio of boron nitride nanotubes to modified nano-ZnO is 1.8-2:1, and the amount of curing agent added is 20-25% of the mass of the ternary epoxy resin blend system.

4. The BGA packaging process for a memory product according to claim 2, characterized in that: The mass ratio of ZnO to dopamine is 10:

1.

5. The BGA packaging process for a memory product according to claim 2, characterized in that: The volume ratio of SiH to CH in the SiH4 and CH4 mixed gas is 1:

4.

6. The BGA packaging process for a memory product according to claim 1, characterized in that: The other additives include aluminum borate whiskers and fumed silica. The amount of aluminum borate whiskers added is 3-5% of the mass of the ternary epoxy resin blend system, and the amount of fumed silica added is 0.3-0.5% of the mass of the ternary epoxy resin blend system.

7. The BGA packaging process for a memory product according to claim 1, characterized in that: The ternary epoxy resin blend system comprises the following components: polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin, wherein the mass ratio of polyurethane modified epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin is 1:3-5:

1.

8. The BGA packaging process for a memory product according to claim 7, characterized in that: The curing agent includes QNP1 type low-temperature latent epoxy resin curing agent and acid anhydride curing agent, with a mass ratio of QNP1 type low-temperature latent epoxy resin curing agent to acid anhydride curing agent of 2:

1.

9. The BGA packaging process for a memory product according to claim 8, characterized in that: The curing method for step S4 is as follows: first heat to 80-85℃, hold the temperature for 5 minutes, then continue to heat to 120℃-130℃ and hold for another 8-10 minutes.

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