Preparation method and application of epoxy phenolic cardamom semiconductor sealant

Abstract

The invention relates to the technical field of preparation of semiconductor sealants, in particular to a preparation method and application of an epoxy phenolic cardamom semiconductor sealant. Stirring, heating and polycondensing methyl phenyl propyl ester and modified mixed phenol to obtain modified epoxy phenolic resin; defoaming under a vacuum condition; stirring and mixing the mixture with compound benzotriazole and a silane coupling agent to prepare a semi-finished product of the semiconductor sealant; and adding carbon black and silicon carbide, and reacting to prepare the epoxy phenolic cardamom semiconductor sealant. The phenolic resin is modified by introducing a natural product methyl phenyl propyl ester, so that the flexibility of the resin is effectively improved, the resin is more suitable for thermal stress change in the packaging process, and the cracking risk is reduced. By adding conductive fillers such as carbon black and silicon carbide, the conductivity of the sealant is improved. The sealant prepared by the invention has flexibility, high temperature resistance and conductivity adjustability, can be widely applied to the fields of advanced semiconductor packaging, power electronic devices, high-reliability sensors and the like, and has a wide market prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor sealant preparation, and more particularly to a preparation method and application of an epoxy phenolic and corundum semiconductor sealant. Background Art

[0002] As electronic devices progress toward miniaturization, higher performance, and greater integration, semiconductor packaging technology places higher demands on materials' heat resistance, sealing, and reliability. As a key component of traditional packaging materials, optimizing the thermal stability of phenolic resins has become a research priority. In recent years, the introduction of conjugated structures, bulky groups, or specialized backbones (such as biphenyl structures) into epoxy resin systems has significantly improved the material's high-temperature resistance and processing characteristics. Biphenyl-based epoxy resins, with their low melt viscosity and excellent adhesion, have demonstrated unique advantages in addressing cracking in semiconductor surface packaging. Furthermore, the natural polymer lignin, due to its abundant hydroxyl and phenolic hydroxyl groups in its three-dimensional network and the presence of cinnamaldehyde-based active components, has potential application in environmentally friendly sealants. Furthermore, 107 silicone rubber, due to its outstanding weather resistance and wide temperature stability, has been widely used in the protection of sensitive components in various fields. However, high-end bonding sealant materials for advanced semiconductor packaging still need to solve the problem of synergistic optimization of resin matrix and key additives such as solvents and antioxidants. Currently, this technology is still in the R&D breakthrough stage, and there is an urgent need to develop a new composite material system with excellent thermal stability, interface bonding strength and process adaptability. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one aspect of the present invention is to provide a method for preparing an epoxy novolac semiconductor sealant. The specific steps of the preparation method are as follows: S1. Under intelligent control, methylphenyl propyl ester (cinnamaldehyde) and modified mixed phenol are added to a high-speed mixing reactor, stirred and heated, and polycondensed to form a low-polymerization-degree modified epoxy phenolic resin with improved flexibility and heat resistance; S2. The modified epoxy phenolic resin prepared in S1 was degassed under vacuum conditions; S3 S2 degassing treatment of modified epoxy phenolic resin, composite benzo coronet and silane coupling agent stirred and mixed to form a semi-finished semiconductor sealant; S4. Add carbon black and silicon carbide to the semi-finished semiconductor sealant prepared in S3 to improve the antistatic properties of the sealant. After the reaction is completed, an epoxy phenolic resin semiconductor sealant is prepared.

[0004] Preferably, the intelligently controlled PC computer system in S1 is adaptively adjusted with the encoder and decoder of the model; wherein, the encoder targets the difference between the original input data and the reconstructed data, and the decoder operates in the opposite order, through instrument monitoring data and machine learning including a multivariate linear regression model, a reinforcement learning model and a support vector machine (SVM), and a dynamic adjustment of the heating process based on point-to-point temperature iterative learning control, through temperature, pressure, and viscosity sensors, the significance of functional characteristics is enhanced, and the application site is regulated in the form of prior information.

[0005] Preferably, the modified mixed phenol in S1 is phenol-m-cresol.

[0006] Preferably, the mass ratio of methylphenyl propyl ester (cinnamaldehyde) to modified mixed phenol in S1 is 0.75-1:1-2.

[0007] Preferably, the speed of the high-speed mixing reactor in S1 is 1000 rpm / min~2000 rpm / min, the stirring time is 0.2h~0.5h, the heating temperature is 25°C~40°C, and the heating time is 0.2h~0.5h.

[0008] Preferably, the vacuum degree in S2 is 0.01MPa~-0.095MPa, and the degassing time is 5min~10min.

[0009] Preferably, the composite benzocoronet in S3 is hexabenzocoronet, and the silane coupling agent is silane coupling agent-KH550.

[0010] Preferably, the mass ratio of the modified epoxy phenolic resin, the composite benzocoronene and the silane coupling agent in S3 is 3:2:1, the reaction temperature is 25°C to 40°C, and the reaction time is 0.5h to 1.0h.

[0011] Preferably, the mass ratio of carbon black and silicon carbide in S4 is 4:1, the mass ratio of the semiconductor sealant semi-finished product, carbon black and silicon carbide is 7~8.5:1~1.5:0.5~1, the reaction temperature is 25℃~40℃, and the reaction time is 1h~2h.

[0012] Another aspect of the present invention is to provide an application of an epoxy novolac and colloidal semiconductor sealant, wherein the epoxy novolac and colloidal semiconductor sealant is used in semiconductor chip packaging, wherein the withstand voltage of the semiconductor chip is ≤1000V~1200V, the chip thickness is ≤0.2mm~0.3mm, the insulation strength of the sealant is >10kV / mm~15kV / mm, and the maximum operating temperature of the chip is >120℃~150℃.

[0013] The beneficial effects of the present invention are as follows: The present invention modifies phenolic resin by introducing the natural product methylphenyl propyl ester (cinnamaldehyde), effectively improving the resin's flexibility, making it more adaptable to thermal stress changes during the packaging process and reducing the risk of cracking. The use of benzocoronet, the smallest structural unit of graphene, as a reinforcing component significantly improves the sealant's high-temperature resistance, making it suitable for the packaging needs of high-power semiconductor devices. By optimizing the composite system of epoxy phenolic base material, benzocoronet, and silane coupling agent, the sealant's curing behavior, bonding strength, and thermal expansion coefficient can be controlled and adjusted to meet the high-precision requirements of semiconductor packaging. By adding conductive fillers such as carbon black and silicon carbide, the sealant's electrical conductivity is improved, making it suitable for electronic packaging scenarios requiring electromagnetic shielding or electrostatic protection.

[0014] Through key performance tests such as tensile modulus, shear strength, and thermal expansion coefficient, it is proved that the sealant has excellent mechanical strength, thermal stability, and long-term reliability, and can meet the strict requirements of the electronics industry for high-performance packaging materials. The epoxy phenolic and phenolic semiconductor sealant prepared by the present invention has flexibility, high temperature resistance, and adjustable conductivity. It can be widely used in advanced semiconductor packaging, power electronic devices, high-reliability sensors and other fields, and has broad market prospects.

[0015] Additional aspects and advantages of the invention will become apparent from the description which follows, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which: Figure 1 is the modified epoxy novolac resin structure characterized by GC-MS in the embodiment of the present invention; Figure 2 is the composite benzocoronet structure characterized by GC-MS in an embodiment of the present invention; Figure 3 The material dynamic weight loss temperature of the epoxy phenolic and phenol semiconductor sealant controlled by a thermogravimetric analyzer according to the embodiment of the present invention is as follows; Figure 4 It is the dynamic weight loss temperature of the material regulated by the thermogravimetric analyzer of the diepoxy phenolic and corundum semiconductor sealant in the embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0018] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from the description. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0019] The intelligently controlled PC system adaptively adjusts the model's encoder and decoder. The encoder targets the difference between the original input data and the reconstructed data, while the decoder operates in the opposite order. It dynamically adjusts the heating process based on instrument monitoring data and machine learning, including multivariate linear regression models, reinforcement learning models, and support vector machines (SVMs), as well as point-to-point temperature iterative learning control. Temperature, pressure, and viscosity sensors enhance the significance of functional features, providing prior information for on-site control. Operation is performed on a 2D+3D vision system, a linear scan vision system, a PC, and an instrument feedback detection system, with quality control performed in accordance with GB / T 2943-2018.

[0020] like Figure 1 and Figure 2 Shown are the modified epoxy phenolic resin structure characterized by GC-MS and the composite benzocoronet structure characterized by GC-MS in an embodiment of the present invention.

[0021] Example 1 S1. Under an intelligent control program, cinnamaldehyde (provided by Shanghai Jizhi Biochemical Technology Co., Ltd.) and phenol-m-cresol at a mass ratio of 0.75:1 were added to a high-speed mixing reactor at 2000 rpm. The mixture was stirred for 30 minutes and heated at 25°C for 0.5 hours to form a low-polymerization-degree modified epoxy novolac resin with improved flexibility and heat resistance. S2. The modified epoxy phenolic resin prepared in S1 was degassed under vacuum conditions of -0.095 MPa for 10 min; S3. The modified epoxy phenolic resin degassed in S2, hexabenzocoronene, and silane coupling agent KH550 were mixed in a mass ratio of 3:2:1 and stirred at 25°C for 60 minutes to prepare a semi-finished semiconductor sealant; S4. Add carbon black and silicon carbide to the semi-finished semiconductor sealant prepared in S3. The mass ratio of the semi-finished semiconductor sealant, carbon black and silicon carbide is 8.5:1:0.5. React at 25℃~40℃ for 1h to improve the antistatic properties of the sealant. After the reaction is completed, epoxy phenolic resin semiconductor sealant is prepared. When it is not cured, it needs to be stored in the dark at -30~0℃ to prevent pre-curing.

[0022] The tensile modulus and shear strength of the product were measured on a tensile testing machine. The tensile modulus and shear strength were 2MPa, and the coefficient of thermal expansion (CTE) was <20ppm / ℃. Figure 3As shown, in the thermogravimetric analyzer, the test was performed with a temperature rise rate of 5°C / min, nitrogen as the protective gas, and a gas flow rate of 60ml / min within the range of 25°C-500°C. Figure 4 (Red line) It can be seen that the mass drops sharply at 300℃-400℃, and the mass begins to stabilize at 450℃. At 380℃, the mass is 72% of the initial mass, indicating that the organic components are basically decomposed and volatilized below 380℃; the blue dotted line in the figure represents the recovery of volatile components at different temperatures.

[0023] Example 2 S1. Under an intelligent control program, cinnamaldehyde (provided by Shanghai Jizhi Biochemical Technology Co., Ltd.) and phenol-m-cresol were added to a high-speed mixing reactor at a mass ratio of 1:2 at 1000 rpm. The mixture was stirred for 0.5 h and heated at 40°C for 0.5 h to form a low-polymerization-degree modified epoxy novolac resin with improved flexibility and heat resistance. S2. The modified epoxy phenolic resin prepared in S1 was degassed under vacuum conditions of -0.1MPa for 15min; S3. The modified epoxy phenolic resin degassed in S2, the composite benzocoronet hexabenzocoronet, and the silane coupling agent KH550 were mixed in a mass ratio of 3:2:1 and stirred at 40°C for 60 minutes to prepare a semi-finished semiconductor sealant; S4. Add silicon carbide to the semi-finished semiconductor sealant prepared in S3. The mass ratio of the semi-finished semiconductor sealant, carbon black and silicon carbide is 8:1:1. The mixture is reacted at 30°C for 1 hour to improve the antistatic properties of the sealant. After the reaction is completed, an epoxy phenolic resin semiconductor sealant is prepared. When it is not cured, it needs to be stored in the dark at -30~0°C to prevent pre-curing.

[0024] The tensile modulus and shear strength of the product are measured on a tensile testing machine. The tensile modulus and shear strength are 3MPa, and the coefficient of thermal expansion (CTE) is <10ppm / ℃. The tensile modulus and shear strength of the product are measured on a tensile testing machine (according to GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber"), and the tensile modulus and shear strength are 3Mpa. For example, the shear strength of the material joint is tested using an IC package solder strength tester (SERIES-4000). The maximum thrust range is 100kg, the pusher speed is 200μm / s, and the pusher height is 1 / 3 of the sample thickness. The shear strength value is calculated using the formula M=F / A (where M is the shear strength (MPa), F is the pusher thrust (N), and A is the contact area (m 2 ).

[0025] The coefficient of thermal expansion (CTE) is less than 10ppm / °C, measured using a DIL402C dilatometer manufactured by NETZSCH (Germany). Under an argon atmosphere, the temperature is raised from 25°C to 300°C at a rate of 10K / min. Cooling is performed using a furnace-cooled method. The thermal strain curves of the samples are then compared to a standard Al2O3 sample, yielding the thermal expansion coefficients of the composites at different temperatures.

[0026] like Figure 4 As shown, in the thermogravimetric analyzer, the test was performed with a temperature rise rate of 5°C / min, nitrogen as the protective gas, and a gas flow rate of 60ml / min within the range of 25°C-500°C. Figure 4 (Red line) It can be seen that the mass drops sharply at 300℃-400℃, and the mass begins to stabilize at 450℃. At 390℃, the mass is 73% of the initial mass, indicating that the organic components are basically decomposed and volatilized below 390℃. The blue dotted line in the figure represents the recovery of volatile components at different temperatures).

[0027] This invention is used to finalize the plastic encapsulation of processed semiconductors. Semiconductor encapsulation provides support for the chip, improving its connection to the circuit; it also strengthens support for the device by fixing its shape, ensuring it is less susceptible to damage. The chemical structure of the modified epoxy resin, composite benzocoronene, and silane coupling agent KH550 before curing is characterized by the presence of two or more active groups, such as oxy, thiol, vinyl, epoxy, amide, and aminopropyl groups. The bond can be formed at temperatures as low as -150°C and as high as 200°C, enabling bonding and encapsulating semiconductor chips.

[0028] Using Jiangsu Kunshan Dual Bridge Sensor CYG500 - micro, thin dynamic pressure sensor - measurement and control, the withstand voltage of the semiconductor chip is ≤1000V~1200V, the chip thickness is ≤0.2mm~0.3mm (known through measurement), the insulation strength of the sealant is >10kV / mm~15kV / mm (the insulation strength of the sealing material is related to airtightness and insulation, and is also measured and controlled by CYG500 - micro, thin dynamic pressure sensor), and the maximum operating temperature of the chip is >120℃~150℃ (it can also be seen from thermogravimetric analysis that the glass transition temperature of the encapsulation glue is >200℃).

[0029] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for preparing an epoxy novolac semiconductor sealant, characterized in that: The specific steps of the preparation method are as follows: S1. Under the intelligent control program, methyl phenyl propyl ester and modified mixed phenol were added to a high-speed mixing reactor, stirred and heated to form a modified epoxy phenolic resin; S2. The modified epoxy phenolic resin prepared in S1 was degassed under vacuum conditions; S3 S2 degassing treatment of modified epoxy phenolic resin, composite benzo coronet and silane coupling agent stirred and mixed to form a semi-finished semiconductor sealant; S4. Add carbon black and silicon carbide to the semi-finished semiconductor sealant prepared in S3, and complete the reaction to produce epoxy phenolic resin semiconductor sealant.

2. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The intelligently controlled PC computer system in S1 is adaptively adjusted using the encoder and decoder of the model; wherein the encoder targets the difference between the original input data and the reconstructed data, and the decoder operates in the opposite order. The temperature rise process is dynamically adjusted based on instrument monitoring data and machine learning, including a multivariate linear regression model, a reinforcement learning model, and a support vector machine, as well as point-to-point temperature iterative learning control. The significance of functional characteristics is enhanced through temperature, pressure, and viscosity sensors, and the application site is regulated in the form of prior information.

3. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The modified mixed phenol in S1 is phenol-m-cresol.

4. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The mass ratio of methyl phenyl propyl ester to modified mixed phenol in S1 is 0.75-1:1-2.

5. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The speed of the high-speed mixing reactor in S1 is 1000 rpm / min~2000 rpm / min, the stirring time is 0.2h~0.5h, the heating temperature is 25°C~40°C, and the heating time is 0.2h~0.5h.

6. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The vacuum degree in S2 is 0.01 MPa to -0.095 MPa, and the degassing time is 5 min to 10 min.

7. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The composite benzocoronet in S3 is hexabenzocoronet, and the silane coupling agent is silane coupling agent-KH550.

8. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The mass ratio of the modified epoxy phenolic resin, the composite benzocoronene and the silane coupling agent in S3 is 3:2:1, the reaction temperature is 25°C to 40°C, and the reaction time is 0.5h to 1.0h.

9. The method for preparing an epoxy novolac semiconductor sealant according to claim 1, wherein: The mass ratio of carbon black to silicon carbide in the S4 is 4:1, the mass ratio of the semiconductor sealant semi-finished product, carbon black and silicon carbide is 7-8.5:1-1.5:0.5-1, the reaction temperature is 25°C-40°C, and the reaction time is 1h-2h.

10. The use of the epoxy novolac semiconductor sealant according to claim 1, characterized in that: The epoxy phenolic and phenolic semiconductor sealant is used in semiconductor chip packaging. The withstand voltage of the semiconductor chip is ≤1000V~1200V, the chip thickness is ≤0.2mm~0.3mm, the insulation strength of the sealant is >10kV / mm~15kV / mm, and the maximum operating temperature of the chip is >120℃~150℃.

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