DAF film for functional chip packaging and manufacturing process thereof

Abstract

The invention relates to the technical field of materials, and discloses a DAF film for functional chip packaging and a manufacturing process thereof.The DAF film is manufactured by taking epoxy resin as a base material, mixing the epoxy resin with auxiliary materials such as a modified boron nitride additive and then conducting a curing process, firstly, a reaction type macromolecular antioxidant is prepared in a polycondensation mode, and then the DAF film is prepared through a curing process; the reaction type macromolecular antioxidant structurally contains a large number of hindered phenol antioxidant groups and also contains a large number of hydroxyl functional groups generated by ring-opening polycondensation, so that the reaction type macromolecular antioxidant can participate in the reaction in the curing process of epoxy resin, and the reaction type macromolecular antioxidant can be used for preparing the modified boron nitride additive. The hexagonal boron nitride can be uniformly dispersed in the DAF film, and the DAF film is endowed with good heat conductivity and high temperature oxidation resistance by utilizing the unique heat conductivity of the boron nitride and the antioxidant effect of the macromolecular antioxidant.

Description

Technical Field

[0001] The invention relates to the technical field of materials, and in particular to a DAF film for functional chip packaging and a manufacturing process thereof. Background Art

[0002] With the rapid development of modern semiconductor technology, chip packaging materials, as an indispensable link in the semiconductor industry chain, are becoming increasingly important. Among them, DAF film (wafer bonding film), as an advanced chip packaging material, has become a star product in the semiconductor packaging field with its unique performance and wide application fields. Since DAF film needs to firmly fix the chip on the substrate to prevent the chip from loosening or falling off during operation, and DAF film cannot have any effect on the electrical properties of the chip, it does not have conductive properties itself. Based on the above, epoxy resin has become a reliable material for making DAF film and has been gradually applied.

[0003] However, in reality, the DAF film needs to effectively transfer the heat generated by the chip to the heat sink to ensure the normal operation of the chip. Therefore, the DAF film also needs to have good thermal conductivity and the ability to continue working under high temperature conditions to prevent high-temperature aging failure from having a negative impact on the storage performance of the chip. However, epoxy resin itself has poor thermal conductivity and poor aging resistance, which leads to great obstacles in its actual application in DAF film. Therefore, it is of great significance to improve the performance of epoxy resin and its further application. Summary of the invention

[0004] In order to solve the problems mentioned in the background technology, the purpose of the present invention is to provide a The purpose of the present invention can be achieved by the following technical solutions: A process for producing a DAF film for functional chip packaging, wherein the DAF film is produced by using raw materials having the following weight fractions: Epoxy resin 52-60 parts; 3-4.5 parts of modified boron nitride additive; 10-20 parts of diluent; Defoaming agent 0.5-1.5 parts; Film-forming aid 0.5-1 part; 20-30 parts of curing agent; 5-10 parts of curing accelerator; The manufacturing process comprises the following steps: The first step is to stir and mix the epoxy resin, modified boron nitride additive, diluent and film-forming aid to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 200-300r / min, mechanically stir for 10-20min, then add the defoamer and mix well, let it stand for 1-2h to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 10-20g / cm 2 After coating, place it in a temperature environment of 100-120°C for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

[0005] As a further embodiment of the present invention, the epoxy resin is bisphenol A epoxy resin or bisphenol F epoxy resin.

[0006] As a further embodiment of the present invention, the specific preparation method of the modified boron nitride additive comprises the following steps: Step S1: Preparation of functionalized hexagonal boron nitride The hydroxylated hexagonal boron nitride is added to acetone, and after being uniformly dispersed by ultrasonication, an acyl chloride modifier is added. After the addition is completed, mechanical stirring is performed at room temperature for 4-8 hours, and solid materials are separated by centrifugation to obtain functionalized hexagonal boron nitride. Step S2: preparing modified boron nitride additive Functionalized hexagonal boron nitride is ultrasonically dispersed in tetrahydrofuran to form a uniform dispersion, and a reactive macromolecular antioxidant is added to the dispersion under ice bath conditions. After the addition is complete, the ice bath is removed, and after stirring at room temperature for 8-12 hours, the material is separated to obtain a modified boron nitride additive.

[0007] As a further embodiment of the present invention, in step S1, the acyl chloride modifier is any one of adipoyl chloride, succinoyl chloride or trimesoyl chloride.

[0008] As a further scheme of the present invention, in step S1, the preparation method of the hydroxylated hexagonal boron nitride is specifically: immersing the hexagonal boron nitride in hydrogen peroxide, ultrasonically treating it at an ultrasonic frequency of 80-100kHz for 20-40min, raising the temperature to 75-85°C, keeping it warm and stirring for 1-2h, then raising the temperature to 90-95°C, keeping it warm for 3-6h, discharging the material, filtering out the solid, washing and vacuum drying.

[0009] As a further embodiment of the present invention, in step S2, the specific preparation method of the reactive macromolecular antioxidant comprises the following steps: Step SS1, adding 3-[bis(glycidyloxymethyl)methoxy]-1,2-propanediol to chloroform, mechanically stirring until completely dissolved, and then continuing to add 3,5-bis(tert-butyl)-4-hydroxyphenylpropanoyl chloride under ice bath conditions, after the addition is completed, stirring at room temperature for 3-6 hours, evaporating to remove the solvent, collecting the product, and obtaining an intermediate product; Step SS2, adding the intermediate product to toluene, stirring to form a uniform reaction liquid, and then continuing to add diglycolic acid and a phase transfer catalyst. After the addition is completed, nitrogen is introduced for protection, and then the temperature is increased to 70-80°C, and after heat treatment for 12-18h, the temperature is lowered and the material is discharged to obtain a reactive macromolecular antioxidant.

[0010] As a further embodiment of the present invention, in step SS1, the molar ratio of 3-[bis(glycidyloxymethyl)methoxy]-1,2-propanediol to 3,5-bis(tert-butyl)-4-hydroxyphenylpropanoyl chloride is 1:2.

[0011] As a further embodiment of the present invention, in step SS2, the phase transfer catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride or tetrabutylammonium hydrogen sulfate.

[0012] As a further embodiment of the present invention, the diluent is any one of neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether or p-tert-butylphenyl glycidyl ether; the defoamer is polyether-modified polysiloxane; the film-forming aid is propylene glycol methyl ether; the curing agent is an acid anhydride curing agent; and the curing accelerator is an imidazole curing accelerator.

[0013] A DAF film for functional chip packaging is produced by adopting the production process.

[0014] Beneficial effects of the present invention: The invention utilizes a polycondensation method to prepare a reactive macromolecular antioxidant. The reactive macromolecular antioxidant structure contains a large number of hindered phenol antioxidant groups and a large number of hydroxyl functional groups generated by ring-opening polycondensation, which can participate in the reaction during the curing process of the epoxy resin. Not only can the formed DAF film contain a large number of hindered phenol antioxidant groups, which greatly improves the aging resistance of the DAF film, but also hexagonal boron nitride can be firmly embedded in the epoxy resin matrix in a chemical bond connection method, thereby improving the interface bonding force between the hexagonal boron nitride and the epoxy resin, and enabling the hexagonal boron nitride to be uniformly dispersed in the DAF film. The unique thermal conductivity of the boron nitride is utilized to form a stable thermal conduction path in the DAF film, thereby producing a good thermal conduction effect.

[0015] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0017] Figure 1 This is the infrared analysis test diagram of reactive macromolecular antioxidant. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Preparation Example 1 Preparation of modified boron nitride additives: Step S1: Hydroxylation modification of hexagonal boron nitride Immerse 3g of hexagonal boron nitride in 30% hydrogen peroxide, ultrasonically treat at 100kHz for 30min, then raise the temperature to 80℃, keep stirring for 2h, then raise the temperature to 90℃, keep warm for 4h, discharge, filter out the solid, wash and vacuum dry; Step S2: Preparation of functionalized hexagonal boron nitride 1.6 g of hydroxylated hexagonal boron nitride was added to acetone, and after being uniformly dispersed by ultrasonication, 2 g of trimesoyl chloride was added. After the addition was completed, mechanical stirring was performed at room temperature for 6 hours, and the solid material was separated by centrifugation to obtain functionalized hexagonal boron nitride. Step S3: preparing modified boron nitride additive 1.2 g of functionalized hexagonal boron nitride was ultrasonically dispersed in tetrahydrofuran to form a uniform dispersion. 2.5 g of reactive macromolecular antioxidant was added to the dispersion under ice bath conditions. After the addition, the ice bath was removed and the material was separated after stirring at room temperature for 9 hours to obtain a modified boron nitride additive.

[0020] The preparation method of the reactive macromolecular antioxidant comprises the following steps: Step SS1, adding 0.3 g of 3-[bis(glycidyloxymethyl)methoxy]-1,2-propanediol to chloroform, mechanically stirring until completely dissolved, and then adding 0.64 g of 3,5-bis(tert-butyl)-4-hydroxyphenylpropanoyl chloride in an ice bath. After the addition is complete, stirring at room temperature for 4 hours, evaporating to remove the solvent, collecting the product, and obtaining an intermediate product; Step SS2, add 0.5g of the intermediate product to toluene, stir to form a uniform reaction solution, then continue to add 0.1g of diglycolic acid and 0.02g of tetrabutylammonium bromide, after the addition is completed, introduce nitrogen protection, then raise the temperature to 75°C, keep warm for 16h, cool and discharge, and the reactive macromolecular antioxidant can be obtained.

[0021] The infrared analysis test of the reactive macromolecular antioxidant is shown in the figure below: Figure 1 As shown, 3271cm -1 The characteristic absorption peak at 3000cm is the characteristic absorption peak of hydroxyl group produced by the ring-opening reaction. -1 ~3100cm -1 The characteristic absorption peak at 1769cm is the characteristic absorption peak of carbon and hydrogen on the benzene ring. -1 and 1736cm -1 The characteristic absorption peak at 1072 cm is the C=O characteristic absorption peak of the ester group. -1 The characteristic absorption peak that appears at is the characteristic absorption peak of the ether bond.

[0022] Example 1 A DAF film for functional chip encapsulation is made of raw materials including the following weight fractions: Epoxy resin 52 parts; 3 parts of modified boron nitride additive; 10 parts of neopentyl glycol diglycidyl ether; 0.5 parts of polyether modified polysiloxane; Propylene glycol methyl ether 0.5 part; 20 parts of curing agent; 5 parts of curing accelerator; The manufacturing process of the DAF film comprises the following steps: The first step is to stir and mix the epoxy resin, modified boron nitride additive, neopentyl glycol diglycidyl ether and propylene glycol methyl ether to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 200r / min, mechanically stir for 20min, then add the polyether-modified polysiloxane and mix well, let it stand for 1h to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 15g / cm 2 After coating, place it in a 100°C temperature environment for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

[0023] The epoxy resin is E44 epoxy resin; the preparation method of the modified boron nitride additive is shown in Preparation Example 1; the curing agent is hexahydrophthalic anhydride; the curing accelerator is 2-heptadecylimidazole, and the same applies to the following.

[0024] Example 2 A DAF film for functional chip encapsulation is made of raw materials including the following weight fractions: Epoxy resin 58 parts; 4 parts of modified boron nitride additive; 1,6-hexanediol diglycidyl ether 15 parts; 1 part of polyether modified polysiloxane; 06 parts of propylene glycol methyl ether; 25 parts of curing agent; 6 parts of curing accelerator; The manufacturing process of the DAF membrane comprises the following steps: The first step is to stir and mix the epoxy resin, modified boron nitride additive, 1,6-hexanediol diglycidyl ether and propylene glycol methyl ether to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 300r / min, mechanically stir for 15min, then add the polyether-modified polysiloxane and mix well, let it stand for 2h to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 15g / cm 2 After coating, place it in a 100°C temperature environment for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

[0025] Example 3 A DAF film for functional chip encapsulation is made of raw materials including the following weight fractions: Epoxy resin 60 parts; 4.5 parts of modified boron nitride additive; 20 parts of tert-butylphenyl glycidyl ether; 1.5 parts of polyether modified polysiloxane; 1 part of propylene glycol methyl ether; 30 parts of curing agent; 10 parts of curing accelerator; The manufacturing process of the DAF film comprises the following steps: The first step is to stir and mix the epoxy resin, modified boron nitride additive, tert-butylphenyl glycidyl ether and propylene glycol methyl ether to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 300r / min, mechanically stir for 10min, then add the polyether-modified polysiloxane and mix well, let it stand for 2h to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 15g / cm 2 After coating, place it in a 120°C temperature environment for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

[0026] Comparative Example 1 A DAF film for functional chip encapsulation is made of raw materials including the following weight fractions: Epoxy resin 58 parts; 4 parts of hexagonal boron nitride; 1,6-hexanediol diglycidyl ether 15 parts; 1 part of polyether modified polysiloxane; 06 parts of propylene glycol methyl ether; 25 parts of curing agent; 6 parts of curing accelerator; The manufacturing process of the DAF film comprises the following steps: The first step is to stir and mix epoxy resin, hexagonal boron nitride, 1,6-hexanediol diglycidyl ether and propylene glycol methyl ether to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 300r / min, mechanically stir for 15 minutes, then add the polyether-modified polysiloxane and mix well, let it stand for 2 hours to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 15g / cm 2 After coating, place it in a 100°C temperature environment for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

[0027] Comparative Example 2 A DAF film for functional chip encapsulation is made of raw materials including the following weight fractions: Epoxy resin 58 parts; 4 parts of reactive macromolecular antioxidant; 1,6-hexanediol diglycidyl ether 15 parts; 1 part of polyether modified polysiloxane; 06 parts of propylene glycol methyl ether; 25 parts of curing agent; 6 parts of curing accelerator; The manufacturing process of the DAF film comprises the following steps: The first step is to stir and mix the epoxy resin, modified boron nitride additive, 1,6-hexanediol diglycidyl ether and propylene glycol methyl ether to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 300r / min, mechanically stir for 15min, then add the polyether-modified polysiloxane and mix well, let it stand for 2h to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 15g / cm 2After coating, place it in a 100°C temperature environment for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

[0028] Test Case Various performance tests were performed on the DAF membranes in the examples and comparative examples, and the results are recorded in Table 1: Table 1 - Test results

[0029] The 180° peel strength test method refers to the standard GB / T 2792-1998. After the test, the value is recorded as the value before heat treatment. The samples of the same batch are tested after accelerated aging at a temperature of 150°C for 12 hours, and the value is recorded as the value after heat treatment. By comparing the reduction in peel strength before and after heat treatment, the high temperature aging resistance of the sample can be judged. Generally speaking, the smaller the reduction, the better the high temperature aging resistance. The test method of thermal conductivity refers to the standard GB.T 3399-1982.

[0030] The test results show that the use of the modified boron nitride additive in Preparation Example 1 of the present invention as an auxiliary material can make the final DAF membrane have more excellent high temperature aging resistance and thermal conductivity.

[0031] After the modified boron nitride additive is replaced with unmodified hexagonal boron nitride, there may be interface problems, the hexagonal boron nitride agglomerates, and fails to form a continuous heat conduction path, resulting in a decrease in the thermal conductivity of the DAF membrane. In addition, the cross-linking effect of the reactive macromolecular antioxidant is lost, the cross-linking density becomes lower, and the cohesive force decreases, which also has a certain negative impact on the bonding performance of the DAF membrane.

[0032] After the modified boron nitride additive is replaced by a reactive macromolecular antioxidant, the advantages of hexagonal boron nitride cannot be utilized, resulting in a significant decrease in the thermal conductivity of the DAF membrane.

[0033] Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas, including the best mode, and also enable any technician in the field to practice the present invention, including making and using any device or system, and implementing any combined method. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements similar to the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, then these other embodiments should also be included in the scope of the claims.

[0034] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A process for producing a DAF film for functional chip packaging, characterized in that: The DAF membrane is made of raw materials including the following weight fractions: Epoxy resin 52-60 parts; 3-4.5 parts of modified boron nitride additive; 10-20 parts of diluent; Defoaming agent 0.5-1.5 parts; Film-forming aid 0.5-1 part; 20-30 parts of curing agent; 5-10 parts of curing accelerator; The manufacturing process comprises the following steps: The first step is to stir and mix the epoxy resin, modified boron nitride additive, diluent and film-forming aid to form a uniform mixture, then add the curing agent and curing accelerator to the mixture, control the stirring rate to 200-300r / min, mechanically stir for 10-20min, then add the defoamer and mix well, let it stand for 1-2h to form an adhesive; Second, apply the adhesive on a clean glass plate and control the amount of adhesive to 10-20g / cm 2 After coating, place it in a temperature environment of 100-120°C for curing. After it is completely cured, take it out, let it stand and cool, and then demold it to get the DAF film.

2. The process for producing a DAF film for functional chip packaging according to claim 1, characterized in that: The epoxy resin is bisphenol A epoxy resin or bisphenol F epoxy resin.

3. The process for producing a DAF film for functional chip packaging according to claim 1, characterized in that: The specific preparation method of the modified boron nitride additive comprises the following steps: Step S1: Preparation of functionalized hexagonal boron nitride The hydroxylated hexagonal boron nitride is surface modified by using an acyl chloride modifier to obtain functionalized hexagonal boron nitride; Step S2: preparing modified boron nitride additive The modified boron nitride additive is prepared by using tetrahydrofuran as a medium and a reactive macromolecular antioxidant to react with functionalized hexagonal boron nitride.

4. The process for producing a DAF film for functional chip packaging according to claim 3, characterized in that: In step S1, the acyl chloride modifier is any one of adipoyl chloride, succinoyl chloride or trimesoyl chloride.

5. The process for producing a DAF film for functional chip packaging according to claim 3, characterized in that: In step S1, the preparation method of the hydroxylated hexagonal boron nitride is specifically as follows: immersing the hexagonal boron nitride in hydrogen peroxide, ultrasonically treating it at an ultrasonic frequency of 80-100kHz for 20-40min, raising the temperature to 75-85°C, keeping it warm and stirring for 1-2h, then raising the temperature to 90-95°C, keeping it warm for 3-6h, discharging the material, filtering out the solid, washing and vacuum drying.

6. The process for producing a DAF film for functional chip packaging according to claim 3, characterized in that: In step S2, the specific preparation method of the reactive macromolecular antioxidant comprises the following steps: Step SS1, using 3-[bis(glycidyloxymethyl)methoxy]-1,2-propanediol and 3,5-bis(tert-butyl)-4-hydroxyphenylpropanoyl chloride as raw materials, and performing a condensation reaction to obtain an intermediate product; Step SS2: using diglycolic acid and the intermediate product to undergo ring-opening polycondensation under the action of a phase transfer catalyst to obtain a reactive macromolecular antioxidant.

7. The process for producing a DAF film for functional chip packaging according to claim 6, characterized in that: In step SS1, the molar ratio of the 3-[bis(glycidyloxymethyl)methoxy]-1,2-propanediol to 3,5-bis(tert-butyl)-4-hydroxyphenylpropanoyl chloride is 1:

2.

8. The process for producing a DAF film for functional chip packaging according to claim 6, characterized in that: In step SS2, the phase transfer catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride or tetrabutylammonium hydrogen sulfate.

9. The process for producing a DAF film for functional chip packaging according to claim 1, characterized in that: The diluent is any one of neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether or p-tert-butylphenyl glycidyl ether; the defoamer is polyether-modified polysiloxane; the film-forming aid is propylene glycol methyl ether; the curing agent is an acid anhydride curing agent; and the curing accelerator is an imidazole curing accelerator.

10. A DAF film for functional chip packaging, characterized in that: The method is prepared by the manufacturing process as described in any one of claims 1 to 9.

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