CN118389111A - A bottom filling glue capable of reducing glue overflow, and its preparation method and application - Google Patents

Abstract

The application discloses an underfill capable of reducing glue overflow, a preparation method and application thereof, wherein the underfill comprises the following raw materials: 52.5-62.5 parts by mass of micron-sized silicon dioxide, 0.5-1.5 parts by mass of nano-sized silicon dioxide, 20.5-28 parts by mass of modified epoxy resin, 15-19 parts by mass of curing agent and 0.2-0.4 part by mass of wetting agent; wherein the modified epoxy resin is obtained by curing and modifying bisphenol A epoxy resin or polyfunctional epoxy resin by a tertiary amine accelerator. The underfill has good working performance; and the glue overflow length is obviously shortened, which indicates that the phenomenon of large glue overflow can be avoided.

Description

A bottom filling glue capable of reducing glue overflow, and its preparation method and application

Technical Field

The present application relates to the technical field of semiconductor chip bottom filling glue, and in particular to a bottom filling glue capable of reducing the amount of glue overflow, and a preparation method and application thereof.

Background technique

In the process of semiconductor chip packaging, bottom filler is usually used to fill the bottom of the chip. After heating and curing, a filling layer is formed to fill the gap at the bottom of the chip. However, the bottom filler often overflows during the packaging process. The so-called overflow phenomenon refers to the colloid flowing out of the packaging area and solidifying. The overflow will increase the total thickness of the chip. Especially when the overflow amount is large, it may cause the chip size to exceed the design requirements, thereby affecting the application of the chip in electronic devices.

Summary of the invention

The purpose of the present application is to provide a bottom filling glue capable of reducing the amount of glue overflow, a preparation method thereof and an application thereof.

On one hand, the present application provides an underfill adhesive that can reduce the amount of overflow, and the raw materials thereof include:

52.5-62.5 parts by mass of micron-sized silicon dioxide, 0.5-1.5 parts by mass of nano-sized silicon dioxide, 20.5-28 parts by mass of modified epoxy resin, 15-19 parts by mass of curing agent, and 0.2-0.4 parts by mass of wetting agent; wherein the modified epoxy resin is obtained by ripening and modifying bisphenol A epoxy resin or multifunctional epoxy resin with a tertiary amine accelerator.

In some specific embodiments, the modified epoxy resin is obtained by ripening and modifying 20 to 28 parts by weight of bisphenol A epoxy resin or multifunctional epoxy resin with 0.4 to 0.6 parts by weight of tertiary amine accelerator.

In some specific embodiments, the modified epoxy resin is prepared by taking a tertiary amine accelerator and an epoxy resin and premixing them, keeping the premix at 90° C. to 110° C. for 1.5 h to 2 h, and then cooling to room temperature to obtain the modified epoxy resin.

In some specific embodiments, the particle size of the micron-sized silica is 0.5 um to 3.5 um.

In some specific embodiments, the particle size of nano-scale silica is 7 nm to 40 nm.

In some specific embodiments, the curing agent is an amine curing agent.

In some embodiments, the wetting agent is a silicone wetting agent.

In some specific implementations, the bottom filling glue further includes 0.1-0.2 parts by mass of pigment.

On the other hand, the present application also provides a method for preparing the above-mentioned bottom filling glue capable of reducing the amount of glue overflow, comprising:

(1) Premixing nano-sized silicon dioxide and modified epoxy resin according to parts by mass to obtain a premix;

(2) taking micron-sized silicon dioxide, a curing agent, and a wetting agent according to weight proportions, and premixing them together with the premix again to obtain a colloid;

(3) Using three rollers to disperse the colloid;

(4) The dispersed colloid is subjected to vacuum degassing to obtain a bottom filling glue product.

On the other hand, the present application provides the use of the bottom filling glue capable of reducing the amount of glue overflow in bottom filling of a semiconductor chip.

In the present application, the inorganic filler is compounded by micron-sized silica and nano-sized silica in a specific ratio. Nano-sized silica can better fill the gaps between micron-sized silica, thereby preventing the resin from flowing out; at the same time, the large specific surface area of nano-sized silica is conducive to increasing the chance of combining with the resin matrix, thereby inhibiting the overflow of the resin. In the present application, the modified epoxy resin uses a tertiary amine promoter that has a higher affinity with the epoxy resin as a modifier. After the modification, the molecular weight and viscosity of the epoxy resin are increased, the adhesion between the resin and the inorganic filler is also increased, and the movement of the resin is inhibited, thereby inhibiting the loss and overflow of the resin. In the present application, a specific inorganic filler and a specific modified epoxy resin are used, and the synergistic effect of the two can significantly inhibit the overflow of glue and avoid the phenomenon of large overflow of glue.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

The bottom filling glue of the present application has good working performance; and the overflow length is significantly shortened, indicating that the phenomenon of large overflow can be avoided.

Detailed ways

In order to make the purpose, technical solutions and beneficial effects of the present application more clearly understood, the present application is further described in detail below in conjunction with embodiments.

The bottom filling glue provided in the present application can reduce the amount of glue overflow, and its raw materials include: 52.5~62.5 mass parts of micron-sized silicon dioxide, 0.5~1.5 mass parts of nano-sized silicon dioxide, 20.5~28 mass parts of modified epoxy resin, 15~19 mass parts of curing agent, and 0.2~0.4 mass parts of wetting agent; wherein, the modified epoxy resin is obtained by ripening and modifying bisphenol A epoxy resin or multifunctional epoxy resin with a tertiary amine accelerator.

In the present application, bisphenol A epoxy resin or multifunctional epoxy resin is ripened and modified by a tertiary amine accelerator, the molecular weight and viscosity of the resin matrix are increased, the adhesion between the resin matrix and the inorganic filler is also increased, the movement of the resin is inhibited, and it helps to inhibit glue overflow.

In some specific embodiments, the modified epoxy resin is obtained by ripening and modifying 20 to 28 parts by mass of bisphenol A epoxy resin or multifunctional epoxy resin with 0.4 to 0.6 parts by mass of tertiary amine accelerator; further, the modified epoxy resin is obtained by ripening and modifying 20 to 27.5 parts by mass of bisphenol A epoxy resin or multifunctional epoxy resin with 0.5 parts by mass of tertiary amine accelerator.

A specific modification method of the modified epoxy resin is as follows: taking the tertiary amine accelerator and the epoxy resin according to the usage respectively and premixing them, keeping the premix at 90°C~110°C for 1.5h~2h, and then cooling to room temperature to obtain the modified epoxy resin.

In the present application, micron-sized silica and nano-sized silica form an inorganic filler, wherein the nano-sized silica has a very small particle size and a large specific surface area, which can increase the bonding opportunity and bonding force between the inorganic filler and the resin matrix, and help to inhibit resin overflow; in addition, the nano-sized silica fills the gaps between the micro-sized silica, and can also prevent the resin from flowing out. In some specific embodiments, the particle size of the micro-sized silica is 0.5um~3.5um, and the particle size of the nano-sized silica is 7nm~40nm.

In the present application, the curing agent is preferably an amine curing agent, such as a fatty amine curing agent or an epoxy resin aromatic modified amine curing agent, which is added in a conventional amount. The wetting agent is preferably an organic silicon wetting agent, which is used to reduce the surface tension of the bottom filler, promote the adhesion of the bottom filler on the device surface, and enhance the film-forming property between the bottom filler and the substrate.

In some specific embodiments, the raw materials of the bottom filling glue that can reduce the amount of glue overflow in the present application also include 0.1 to 0.2 parts by weight of a pigment, such as carbon black.

The present application provides a method for preparing the above-mentioned bottom filling glue, comprising:

(5) Add nano-silicon dioxide and modified epoxy resin according to mass parts into a stirring cup for premixing to obtain a premix; in some specific embodiments, the premixing process parameters are: rotation speed 750 r / min , revolution speed 920 r / min , stirring time 60 s to 90 s ;

(6) Take micron-sized silicon dioxide, curing agent, and wetting agent according to mass proportions, add them together with the premix into a stirring cup, and premix them using a centrifugal stirrer to preliminarily mix the raw materials and obtain a colloid; in some specific embodiments, the parameters of the centrifugal stirrer are: rotation speed 750 r / min , revolution speed 920 r / min , stirring time 145 s to 165 s ;

(7) using three rollers to disperse the colloid; in some specific embodiments, the feeding gap of the three rollers is 15 um to 30 um , and the discharging gap is 10 um to 15 um ;

(8) The dispersed colloid is subjected to vacuum degassing to obtain a bottom filling glue product. In some specific embodiments, a centrifugal mixer is used for vacuum degassing. The parameters of the centrifugal mixer are: rotation speed 750 r / min , revolution speed 920 r / min , and degassing time 85 s to 95 s .

Several embodiments and comparative examples are provided below. The raw materials used in the embodiments and comparative examples are as follows:

Micron-sized silica: particle size range 0.5 um ~3.5 um ;

Nano-scale silica: particle size ranges from 7 nm to 40 nm ;

Epoxy resin: Bisphenol A epoxy resin NR -8133 and Bisphenol A epoxy resin YLE -1300A from Nanjing Yuelai New Material Technology Co., Ltd.; Multifunctional epoxy resin ARALDITE MY 0600 from Guangzhou Si Tuyuan Chemical Co., Ltd.;

Curing agent: Shanghai Zhenlishi Network Technology Co., Ltd. epoxy resin aromatic modified amine curing agent Gaskamine 240;

Wetting agent: SP -832 silicone wetting agent from Dongguan Xinbocheng Environmental Protection Materials Co., Ltd., the main component of which is polyether-modified polysiloxane;

Tertiary amine accelerator: K 54 epoxy resin from Shandong Maofa Chemical Co., Ltd.

The examples and comparative examples provided in this application are as follows:

Example 1

The raw materials and the amounts of the raw materials in this embodiment are as follows:

Micron-sized silicon dioxide 58 parts by mass;

0.5 parts by mass of nano-silicon dioxide;

Modified epoxy resin 22 parts by mass;

Curing agent Gaskamine 240 19 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

The modified epoxy resin is obtained by modifying the epoxy resin YLE-1300A with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin YLE-1300A are taken in a mass ratio of 0.5:21.5, first added into a stirring cup for premixing, then kept at 90°C in an oven for 2 hours, and cooled to room temperature along with the oven.

Example 2

The raw materials and the amounts of the raw materials in this embodiment are as follows:

Micron-sized silicon dioxide 57.5 parts by mass;

1 part by mass of nano-scale silicon dioxide;

Modified epoxy resin 25 parts by mass;

Curing agent Gaskamine 240 16 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

Among them, the modified epoxy resin is obtained by modifying the epoxy resin NR-8133 with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin NR-8133 are taken in a mass ratio of 0.5:24.5, first added into a stirring cup for premixing, and then kept at 100°C in an oven for 2 hours, and cooled to room temperature with the furnace.

Example 3

The raw materials and the amounts of the raw materials in this embodiment are as follows:

Micron-sized silicon dioxide: 56 parts by mass;

1.5 parts by mass of nano-silicon dioxide;

Modified epoxy resin 27 parts by mass;

Curing agent Gaskamine 240 15 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

The modified epoxy resin is obtained by modifying epoxy resin ARALDITE MY 0600 with modifier K54 epoxy resin. Specifically, modifier K54 epoxy resin and epoxy resin ARALDITE MY 0600 are taken in a mass ratio of 0.5:26.5, first added into a stirring cup for premixing, then kept at 110° C. for 1.5 hours in an oven, and cooled to room temperature along with the oven.

Example 4

The raw materials and the amounts of the raw materials in this embodiment are as follows:

Micron-sized silicon dioxide 52.5 parts by mass;

1 part by mass of nano-scale silicon dioxide;

Modified epoxy resin 28 parts by mass;

Curing agent Gaskamine 240 18 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

The modified epoxy resin is obtained by modifying epoxy resin ARALDITE MY 0600 with modifier K54 epoxy resin. Specifically, modifier K54 epoxy resin and epoxy resin ARALDITE MY 0600 are taken in a mass ratio of 0.5:27.5, first added into a stirring cup for premixing, then kept at 110° C. for 1.5 hours in an oven, and cooled to room temperature along with the oven.

Example 5

The raw materials and the amounts of the raw materials in this embodiment are as follows:

Micron-sized silicon dioxide 62.5 parts by mass;

1.5 parts by mass of nano-silicon dioxide;

Modified epoxy resin 20.5 parts by mass;

Curing agent Gaskamine 240 15 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

Among them, the modified epoxy resin is obtained by modifying the epoxy resin NR-8133 with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin NR-8133 are taken in a mass ratio of 0.5:20, first added into a stirring cup for premixing, and then kept at 100°C in an oven for 2 hours, and cooled to room temperature with the furnace.

Example 6

The raw materials and the amounts of the raw materials in this embodiment are as follows:

Micron-sized silicon dioxide 55 parts by mass;

0.5 parts by mass of nano-silicon dioxide;

Modified epoxy resin 25 parts by mass;

Curing agent Gaskamine 240 19 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

The modified epoxy resin is obtained by modifying the epoxy resin YLE-1300A with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin YLE-1300A are taken in a mass ratio of 0.5:24.5, first added into a stirring cup for premixing, then kept at 90°C in an oven for 2 hours, and cooled to room temperature along with the oven.

Example 7

The raw materials and the amounts of the raw materials in this embodiment are as follows:

60 parts by mass of micron-sized silicon dioxide;

0.5 parts by mass of nano-silicon dioxide;

Modified epoxy resin 22 parts by mass;

Curing agent Gaskamine 240 17 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

The modified epoxy resin is obtained by modifying the epoxy resin YLE-1300A with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin YLE-1300A are taken in a mass ratio of 0.5:21.5, first added into a stirring cup for premixing, then kept at 90°C in an oven for 2 hours, and cooled to room temperature along with the oven.

Comparative Example 1

The raw materials and the amounts of each raw material used in this comparative example are as follows:

Micron-sized silicon dioxide 58 parts by mass;

Modified epoxy resin 24.5 parts by mass;

Curing agent Gaskamine 240 17 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass;

Among them, the modified epoxy resin is obtained by modifying the epoxy resin NR-8133 with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin NR-8133 are taken in a mass ratio of 0.5:24, first added into a stirring cup for premixing, and then kept at 100°C in an oven for 2 hours, and cooled to room temperature with the furnace.

Comparative Example 2

The raw materials and the amounts of each raw material used in this comparative example are as follows:

Micron-sized silicon dioxide 58 parts by mass;

0.5 parts by mass of nano-silicon dioxide;

Bisphenol A epoxy resin NR-8133 24 parts by mass;

Curing agent Gaskamine 240 17 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass.

Comparative Example 3

The raw materials and the amounts of each raw material used in this comparative example are as follows:

Micron-sized silicon dioxide 66.1 parts by mass;

Nano-scale silicon dioxide 0.4 parts by mass;

Modified epoxy resin 19 parts by mass;

Curing agent Gaskamine 240 14 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass.

Among them, the modified epoxy resin is obtained by modifying the epoxy resin NR-8133 with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin NR-8133 are taken in a mass ratio of 0.3:18.7, first added into a stirring cup for premixing, and then kept at 100°C in an oven for 2 hours, and cooled to room temperature with the furnace.

Comparative Example 4

The raw materials and the amounts of each raw material used in this comparative example are as follows:

Micron-sized silicon dioxide 50.1 parts by mass;

Nano-scale silicon dioxide 0.4 parts by mass;

Modified epoxy resin 29 parts by mass;

Curing agent Gaskamine 240 20 parts by mass;

Wetting agent SP-832 0.3 parts by mass;

Carbon black 0.2 parts by mass.

Among them, the modified epoxy resin is obtained by modifying the epoxy resin NR-8133 with the modifier K54 epoxy resin. Specifically, the modifier K54 epoxy resin and the epoxy resin NR-8133 are taken in a mass ratio of 0.7:28.3, first added into a stirring cup for premixing, and then kept at 100°C in an oven for 2 hours, and cooled to room temperature with the furnace.

The performance parameter detection methods of the products of the embodiments and comparative examples are as follows:

(1) Viscosity:

The room temperature viscosity was measured using a digital rotational viscometer.

(2) Liquidity:

Take a square Si wafer with a width of 20 mm, a length of 20 mm, and a thickness of 0.5 mm, stick the four corners of the Si wafer with 50 um thick double-sided tape and stick it on the substrate, use a dispensing machine to dispense about 35-40 mg of the glue to be tested horizontally along one edge of the Si wafer at room temperature, then place it on a 110°C hot plate and start timing at the same time. Under the action of capillary force, the glue will flow to the bottom of the Si wafer, and record the time taken for the flow to be half full and full respectively.

(3) Glue overflow length:

The Si wafer with glue flowing all over the bottom during the fluidity test was cured at 150°C for 2h, and then the overflow length was measured under an optical microscope.

(4) Thixotropy:

The thixotropic coefficient of the test glue was tested using a rheometer, with a shear rate range of 1-100S-1, a test time of 600s, and a temperature of 110°C.

(5) Surface tension:

Ring method test: at 110℃, place a ring flat on the surface of the glue liquid, measure the maximum force P required to pull the ring away from the glue liquid surface, and calculate the surface tension , where R is the radius of the ring and f is the correction factor.

Table 1 Performance parameters of the products of the embodiments and comparative examples

It can be clearly seen from Table 1 that the overflow length of the products of Comparative Examples 1 to 4 is long, and the overflow length of the products of Examples 1 to 7 is significantly shortened. The present application solves the overflow problem of the bottom filling glue. It can be seen that when the modified epoxy resin is used and a specific amount of nano-silicon dioxide is added at the same time, the overflow of the bottom filling glue can be reduced.

The above embodiments are only for the purpose of clearly illustrating the embodiments, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above descriptions. It is not necessary and impossible to list all the implementation methods here, so the obvious changes or modifications derived are still within the protection scope of the invention.

Claims (10)

1. The underfill capable of reducing the glue overflow amount is characterized by comprising the following raw materials: 52.5-62.5 parts by mass of micron-sized silicon dioxide, 0.5-1.5 parts by mass of nano-sized silicon dioxide, 20.5-28 parts by mass of modified epoxy resin, 15-19 parts by mass of curing agent and 0.2-0.4 part by mass of wetting agent; wherein the modified epoxy resin is obtained by curing and modifying bisphenol A epoxy resin or polyfunctional epoxy resin by a tertiary amine accelerator.

2. The underfill with reduced flash of claim 1, wherein: the modified epoxy resin is prepared by curing and modifying 20-28 parts by mass of bisphenol A epoxy resin or multifunctional epoxy resin by 0.4-0.6 part by mass of tertiary amine accelerator.

3. The underfill with reduced flash of claim 1, wherein: the preparation of the modified epoxy resin comprises the following steps: and (3) taking a tertiary amine accelerator and epoxy resin, premixing, placing the premix at the temperature of 90-110 ℃ for 1.5-2 hours, and cooling to room temperature to obtain the modified epoxy resin.

4. The underfill with reduced flash of claim 1, wherein: the particle size of the micron-sized silicon dioxide is 0.5-3.5 um.

5. The underfill with reduced flash of claim 1, wherein: the particle size of the nanoscale silicon dioxide is 7 nm-40 nm.

6. The underfill with reduced flash of claim 1, wherein: the curing agent is an amine curing agent.

7. The underfill with reduced flash of claim 1, wherein: the wetting agent is an organosilicon wetting agent.

8. The underfill with reduced flash of claim 1, wherein: the underfill adhesive further comprises 0.1-0.2 parts by mass of pigment.

9. The method for preparing the underfill capable of reducing the flash amount according to any one of claims 1 to 8, comprising the steps of:

(1) Premixing nanoscale silicon dioxide and modified epoxy resin according to mass parts to obtain a premix;

(2) Taking micron-sized silicon dioxide, a curing agent and a wetting agent according to parts by mass, and premixing again together with the premix to obtain a jelly;

(3) Dispersing the jelly by using three rollers;

(4) And (3) carrying out vacuum defoamation on the jelly after the dispersion treatment to obtain an underfill product.

10. Use of the underfill composition of any one of claims 1-8 for underfilling semiconductor chips.