A silver conductive adhesive die bonding process and chip mounting method

Abstract

The application relates to the technical field of conductive glue, and particularly discloses a silver conductive glue patching process and a chip mounting method, the silver conductive glue patching process comprises the following steps: S1, dispensing glue, dispensing glue on the surface of a base material; S2, standing, placing the base material after the glue dispensing, and the standing time is T; S3, bonding, bonding a chip to the base material after the standing, so as to realize the patching of the chip and the base material; wherein the standing time T of the base material in the step S2 is determined by the following method: after dispensing glue on the surface of the base material, different time is allowed to elapse, then different chip areas are bonded to the surface of the base material, then curing is carried out, and the standing time T corresponding to the time when the performance of the different chip areas after the curing is qualified is counted; the chip mounting method comprises the following steps: patching, bonding the chip and the base material according to the silver conductive glue patching process; and curing. The application has the characteristics of better realizing the patching of the conductive glue and preventing silver particles from overflowing to the chip.

Description

Technical Field

[0001] This application relates to the technical field of conductive adhesives, and more specifically, to a die bonding process and chip mounting method for silver conductive adhesive. Background Technology

[0002] Chip mounting is the process of fixing a chip onto a package substrate or a chip carrier with lead frames. In chip mounting, conductive adhesive serves as a bonding medium, connecting the chip and the package substrate. The curing of the conductive adhesive enhances the chemical bond between the chip and the substrate, and provides electrical and thermal conductivity. Because silver powder has excellent conductivity and is not easily oxidized, silver-based conductive adhesives are widely used.

[0003] However, the applicant discovered that when using conductive adhesive for die bonding, after applying the adhesive and bonding the die directly, followed by high-temperature curing, silver particles would climb onto the chip sidewalls. When the chip sidewalls had excess silver particles, these excess silver particles would fall off during subsequent product screening processes when subjected to mechanical stress such as vibration or thermal stress, causing abnormal electrical performance or product failure. Summary of the Invention

[0004] In order to better achieve the bonding of conductive adhesive and prevent silver particles from overflowing onto the chip sidewalls, this application provides a bonding process for silver conductive adhesive and a chip mounting method.

[0005] Firstly, the bonding process of the silver conductive adhesive provided in this application adopts the following technical solution: A bonding process for silver conductive adhesive includes the following steps: S1: Dispensing adhesive, dispensing adhesive onto the surface of the substrate; S2: Settling, place the substrate after dispensing for a time of T; S3: Bonding, bonding the chip to the substrate after it has been left to stand, thus achieving chip bonding to the substrate; In step S2, the substrate placement time T is determined by the following method: After applying adhesive to the substrate surface, the chips were left for different durations. Then, chips of different sizes were adhered to the substrate surface and cured under the same conditions. The placement time T corresponding to the performance of different chip sizes after curing was statistically analyzed. The performance was considered acceptable when no conductive adhesive boundary line appeared on the chip sidewall and the chip shear strength was >100N.

[0006] By adopting the above technical solution, the applicant discovered that because the conductive adhesive contains resin-based organic substances such as epoxy resin, if bonding is carried out directly after dispensing the adhesive, the low surface tension of the resin and the strong climbing force of the conductive adhesive cause the organic substances to carry silver particles to climb onto the sidewall of the chip, resulting in excess silver particles remaining on the sidewall of the chip, which leads to chip defects.

[0007] Through experiments, the inventors discovered that after dispensing the adhesive and allowing it to stand for an appropriate period of time, no boundary line formed by the conductive adhesive carrying silver particles was observed on the sidewall of the chip, and the final chip shear strength was >100N, and the bonding strength met the requirements.

[0008] If the settling time after dispensing is too short, the climbing effect of the conductive adhesive will still cause a boundary line to appear on the chip sidewall, and silver particles will appear on the chip sidewall and around the casing. If the settling time after dispensing is too long, as the time increases, a large amount of the thinner in the conductive adhesive will evaporate, causing the resin matrix in the conductive adhesive to cure prematurely due to the lack of thinner barrier. The adhesive will harden, resulting in high resistance to chip bonding, which is not conducive to chip adhesion and ultimately leads to weak chip adhesion (shear strength).

[0009] The settling time varies depending on the chip area. Therefore, through the exploration of settling time and chip area, it was found that different chip areas do not have the required settling time when the adhesion of silver particles meets the requirements. When bonding chips, the settling time is directly based on the chip area. In the end, the chip will not have silver particles overflowing, the product is qualified, and the efficiency is higher.

[0010] Optional, The chip area is ≥1.0 mm². 2 And <3.0mm 2 At that time, the placement time T between dispensing and bonding is 180±10s; The chip area is ≥3.0mm². 2 and <5.0mm 2 At that time, the placement time T between dispensing adhesive and bonding is 250±10s; The chip area is ≥5.0mm². 2 And ≤10.0mm 2 The placement time T between dispensing the adhesive and bonding is 300±10s.

[0011] Optional, The chip area is 1.8 mm². 2 At that time, the placement time T between dispensing and bonding is 180s; The chip area is 4.6 mm². 2 At that time, the placement time T between dispensing adhesive and bonding is 250s; The chip area is 5.4 mm². 2 At that time, the placement time T between dispensing the adhesive and bonding is 300s.

[0012] By adopting the above technical solution, when performing the die bonding process according to the chip area and placement time, the final chip product meets the requirements and has better performance.

[0013] Optionally, the dispensing parameters in step S1 are: dispensing air pressure of 0.4±0.05MPa and dispensing time of 14-15ms.

[0014] Secondly, the chip mounting method provided in this application adopts the following technical solution: A chip mounting method includes the following steps: Gluing: The chip and the substrate are glued together according to the glue bonding process of the silver conductive adhesive; Curing: Then heat up to cure and then cool to room temperature.

[0015] By adopting the above technical solution, the chip and substrate are bonded together and then heated and cured, thereby connecting the substrate and chip with conductive adhesive, and greatly improving the chemical bonding strength between the chip and the substrate after curing.

[0016] Optionally, the heating process in the curing step includes a stepped heating stage and a constant temperature stage performed sequentially. The specific parameters of the stepped heating stage are as follows: First stage: Heat to 120±10℃ and hold for 3-5 minutes; Second stage: Heat to 200±10℃ and hold for 3-5 minutes; Third stage: Raise the temperature to 280±10℃ and hold for 3-5 minutes; The parameters for the isothermal stage are: heat up to 410-430℃ and hold for 8-12 minutes.

[0017] By adopting the above technical solution, the conductive adhesive is stabilized during the heating process by using a stepped heating method. The constant temperature stage is the curing stage of the conductive adhesive. The first and second stages of the stepped heating are to allow the organic matter to volatilize at high temperatures. The third stage reaches the glass transition temperature of the silver conductive adhesive, 250°C, to enable it to rapidly transition. Then, it enters the constant temperature stage, where the conductive adhesive cures. Finally, the chip appearance meets the requirements, with no cracks or peeling, and the shear strength is >100N, which meets the requirements.

[0018] Optionally, the heating rate in the first stage is 10-15℃ / min; The heating rate in the second stage is 20-25℃ / min; The heating rate in the third stage is 30-35℃ / min; The heating rate during the isothermal phase is 15-20℃ / min.

[0019] By adopting the above technical solution and controlling the heating rate, the conductive adhesive is stabilized, resulting in a better bonding effect.

[0020] Optionally, during the curing step, the cooling rate is 6-10°C / min.

[0021] In summary, this application has the following beneficial effects: 1. Allowing the silver conductive adhesive to stand for an appropriate time after dispensing and before bonding ensures that no boundary line is observed on the chip sidewall due to silver particles carried by the conductive adhesive. Furthermore, the final chip shear strength is >100N, and the bonding strength meets the requirements. This solves the problem of silver particle overflow causing product defects due to direct bonding after dispensing. 2. Through exploration of settling time and chip area, it was found that different chip areas do not have the same settling time when the adhesion of silver particles meets the requirements. When bonding chips, the settling time is directly based on the chip area. In the end, the chip will not have silver particles overflowing, the product is qualified, and the efficiency is higher. 3. After the silver conductive adhesive is bonded to the die according to the processing method of this application, a stepped heating method is used to stabilize the adhesive during the heating process. The constant temperature stage is the curing stage of the conductive adhesive. The first and second stages of the stepped heating are to allow the organic matter to volatilize at high temperature. The third stage reaches the glass transition temperature of the silver conductive adhesive, 250°C, to make it transform rapidly. Then, the constant temperature stage is entered, and the conductive adhesive is cured. Finally, the chip appearance meets the requirements, with no cracks or peeling, and the shear strength is >100N, which meets the requirements. Attached Figure Description

[0022] Figure 1 This is an image of the chip after curing with a settling time of 150 seconds, as shown in the embodiment of this application. Figure 2 This is an image of the chip after curing with a settling time of 180 seconds, as shown in the embodiment of this application. Figure 3 This is an image of the chip after curing with a settling time of 200 seconds, as shown in the embodiment of this application. Figure 4 This is a graph showing the temperature change during the curing process in an application example of this application. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that: unless otherwise specified in the following embodiments, the conditions are carried out according to conventional conditions or the conditions recommended by the manufacturer. Unless otherwise specified, the raw materials used in the following embodiments can be obtained from commercially available sources.

[0024] In the following examples, the chip shear strength was tested according to the requirements of GJB548B method 2019.2.

[0025] The conductive adhesive used in this application is model QMI2569, which is a high-temperature silver conductive adhesive. The raw materials contain silver conductive filler, epoxy resin and curing agent. In order to prevent the conductive adhesive from curing too quickly at room temperature, a thinner is usually added to the conductive adhesive. It is precisely because of the addition of thinner to the conductive adhesive that the inventor found that when the time after applying the adhesive to the substrate and before bonding is too long, the thinner evaporates and the epoxy resin and curing agent cure. When pressing the chip onto the substrate during bonding, the resistance is greater and the bonding strength (that is, the chip shear strength) is also lower.

[0026] The applicant found that after the substrate was glued and allowed to stand for an appropriate time before bonding, the resulting chip product would not have the problem of residual silver particles on the chip sidewalls and surrounding the substrate due to the surface tension of the resin matrix, which would cause the silver particles to climb to the chip sidewalls and the surrounding substrate, resulting in product defects; and the chemical bonding force between the chip and the substrate met the requirements.

[0027] However, the applicant discovered that the required resting time varied depending on the chip size. Therefore, the applicant then explored the resting time corresponding to different chip sizes, and the specific operation is as follows: After applying adhesive to the substrate surface, the chips were placed for different time periods with consistent adhesive parameters. Then, chips of different sizes were bonded to the substrate surface and cured under consistent curing conditions. The placement time T corresponding to the performance of different chip sizes after curing was statistically analyzed. The performance was considered acceptable when no conductive adhesive boundary line appeared on the chip sidewall and the chip shear strength was >100N. In the above process, the dispensing parameters are as follows: dispensing air pressure is 0.4±0.05MPa, dispensing time is 14-15ms, and the number of dispensing items forms a dispensing matrix, which corresponds to the chip area. The curing conditions consist of a stepped heating stage, a constant temperature stage, and a cooling stage performed sequentially. The parameters for the stepped isothermal stage are: First stage: Increase the temperature from room temperature to 120±10℃ at a rate of 10-15℃ / min, and hold for 3-5 minutes; Second stage: Heat to 200±10℃ at a rate of 20-25℃ / min, and hold for 3-5 minutes; Third stage: Heat to 280±10℃ at a rate of 30-35℃ / min, and hold for 3-5 minutes; The parameters for the isothermal stage are: heating to 410-430℃, heating rate of 15-20℃ / min, and holding for 8-12 minutes.

[0028] The cooling stage parameters are: cooling to room temperature, with a cooling rate of 6-10℃ / min.

[0029] The applicant's chip area is mainly ≤10.0mm². 2 Therefore, the final settling time T is as follows: Chip area ≥ 1.0 mm² 2 And <3.0mm 2 At that time, the placement time T between dispensing and bonding is 180±10s; Chip area ≥ 3.0 mm² 2 and <5.0mm 2 At that time, the placement time T between dispensing adhesive and bonding is 250±10s; Chip area ≥ 5.0 mm² 2 And ≤10.0mm 2 The placement time T between dispensing the adhesive and bonding is 300±10s. Example

[0030] A bonding process for silver conductive adhesive includes the following steps: S1: Dispensing adhesive. Dispensing adhesive onto the tube shell substrate. Dispensing parameters are: dispensing air pressure 0.4MPa, dispensing time 14ms. S2: Settling. Place the dispensed tube substrate in a static environment for a time T. The settling time T is determined by the following method: After applying adhesive to the surface of the casing substrate, the chips were left for different durations. Different chip sizes were then adhered to the substrate surface and cured under consistent conditions. The placement time T corresponding to the achievement of satisfactory performance after curing was statistically analyzed for different chip sizes. Satisfactory performance was defined as the absence of conductive adhesive demarcation lines on the chip sidewalls and a chip shear strength >100N. The dispensing parameters were: dispensing pressure 0.4MPa, dispensing time 14ms; the curing conditions included a sequential stepped heating stage, a isothermal stage, and a cooling stage. The parameters for the stepped isothermal stage are: First stage: Heat from room temperature to 120℃ at a rate of 10℃ / min, and hold for 5min; Second stage: Heat to 200℃ at a rate of 25℃ / min, and hold for 5 minutes; Third stage: Heat to 280℃ at a rate of 30℃ / min, and hold for 5 minutes; The parameters for the isothermal stage are: heating to 420℃, heating rate of 20℃ / min, and holding for 10min.

[0031] The cooling stage parameters are: cooling to room temperature at a rate of 10℃ / min.

[0032] The statistical results are shown in Table 1 below: Table 1: Additionally, observations were conducted after bonding chips with dimensions of 1.32 x 1.37 mm. Figures 1-3 As shown (the black shaded areas in the image are caused by lighting). Figure 1 The image shows the observation after 150 seconds. It can be seen that there is a clear dividing line of cracks at the edge of the conductive adhesive in the circle. The dividing line is caused by organic matter climbing up and carrying silver particles, which leads to the formation of a dividing line between the organic matter and the conductive adhesive. When the placement time is short, there are silver particles on the side wall of the chip. Figure 2 The image shows the observation after 180 seconds. It can be seen that no boundary line appears, and the chip shear strength is >100N, so the product meets the requirements. Figure 3 The image shows an observation after 200 seconds. A boundary line can be seen between the conductive adhesive and the bottom of the tube shell. This is mainly due to poor adhesion between the conductive adhesive and the bottom of the tube shell. Additionally, the shear strength is low and does not meet product requirements.

[0033] The same tests were performed on chips of other sizes, and some of the test results are shown in Table 2 below: Table 2: It can be seen that when the chip area is ≥1.0mm² 2 And <3.0mm 2 At that time, the placement time T between dispensing and bonding is 180±10s; Chip area ≥ 3.0 mm² 2 and <5.0mm 2 At that time, the placement time T between dispensing adhesive and bonding is 250±10s; Chip area ≥ 5.0 mm² 2 And ≤10.0mm 2 The placement time T between dispensing the adhesive and bonding is 300±10s.

[0034] S3: Bonding, bonding different sizes to the substrate after it has been left to stand, to achieve chip bonding to the substrate.

[0035] Application examples Application Example 1 A chip mounting method includes the following steps: Die bonding: The chip size to be bonded is 1.54*1.63mm, and the chip area is 2.5mm². 2 , The specific steps involved in attaching the film are as follows: S1: Dispensing adhesive. Dispensing adhesive onto the tube shell substrate. Dispensing parameters are: dispensing air pressure 0.4MPa, dispensing time 14ms. S2: Let stand, place the tube shell substrate after dispensing glue for 180 seconds; S3: Bonding, bonding the chip with a chip size of 1.54*1.63mm to the shell substrate after S2 treatment to obtain the chip product; Curing: The bonded chip products are then processed according to... Figure 3 The solidification process involves a stepped heating stage, a constant temperature stage, and a cooling stage, in sequence. Specifically: The parameters for the stepped isothermal stage are: First stage: Heat from room temperature to 120℃ at a rate of 10℃ / min, and hold for 5min; Second stage: Heat to 200℃ at a rate of 25℃ / min, and hold for 5 minutes; Third stage: Heat to 280℃ at a rate of 30℃ / min, and hold for 5 minutes; The parameters for the isothermal stage are: heating to 420℃, heating rate of 20℃ / min, and holding for 10min.

[0036] The cooling stage parameters are: cooling to room temperature at a rate of 10℃ / min.

[0037] It can be observed that no boundary line appears on the sidewall of the chip after curing, and there is no phenomenon of organic matter carrying silver particles climbing. Moreover, the shear strength of the chip after curing is 118.5N>100N, and the product is qualified.

[0038] Application Example 2 A chip mounting method, following the method in Application Example 1, differs in that... During the curing process: The parameters for the stepped isothermal stage are: First stage: Heat from room temperature to 110℃ at a rate of 10℃ / min, and hold for 3 minutes; Second stage: Heat to 190℃ at a rate of 20℃ / min, hold for 3min; Third stage: Heat to 270℃ at a rate of 30℃ / min, and hold for 3 minutes; The parameters for the isothermal stage are: heating to 410℃, heating rate of 15℃ / min, and holding for 8 minutes.

[0039] The cooling stage parameters are: cooling to room temperature at a rate of 6℃ / min.

[0040] It can be observed that no boundary line appears on the sidewall of the chip after curing, and there is no phenomenon of organic matter carrying silver particles climbing. Moreover, the shear strength of the chip after curing is 114.2N>100N, and the product is qualified.

[0041] Application Example 3 A chip mounting method, following the method in Application Example 1, differs in that... During the curing process: The parameters for the stepped isothermal stage are: First stage: Increase the temperature from room temperature to 130℃ at a rate of 15℃ / min, and hold for 5min; Second stage: Heat to 210℃ at a rate of 25℃ / min, and hold for 5 minutes; Third stage: Heat to 290℃ at a rate of 35℃ / min, and hold for 5 minutes; The parameters for the isothermal stage are: heating to 430℃, heating rate of 20℃ / min, and holding for 12min.

[0042] The cooling stage parameters are: cooling to room temperature at a rate of 10℃ / min.

[0043] It can be observed that no boundary line appears on the sidewall of the chip after curing, and there is no phenomenon of organic matter carrying silver particles climbing. Moreover, the shear strength of the chip after curing is 110.8N>100N, and the product is qualified.

[0044] Application Example 4 A chip mounting method includes the following steps: Die bonding: The chip size to be bonded is 1.86*2.34mm, and the chip area is 4.4mm². 2 , The specific steps involved in attaching the film are as follows: S1: Dispensing adhesive. Dispensing adhesive onto the tube shell substrate. Dispensing parameters are: dispensing air pressure 0.4MPa, dispensing time 15ms. S2: Let stand, place the tube shell substrate after glue application for 240 seconds; S3: Bonding, bonding the chip with a chip size of 1.86*2.34mm to the shell substrate after S2 treatment to obtain the chip product; Curing: The bonded chip products undergo a stepped heating stage, a isothermal stage, and a cooling stage sequentially to achieve curing. Specifically: The parameters for the stepped isothermal stage are: First stage: Heat from room temperature to 120℃ at a rate of 10℃ / min, and hold for 5min; Second stage: Heat to 200℃ at a rate of 25℃ / min, and hold for 5 minutes; Third stage: Heat to 280℃ at a rate of 30℃ / min, and hold for 5 minutes; The parameters for the isothermal stage are: heat up to 420℃, 20℃ / min, and hold for 10min.

[0045] The cooling stage parameters are: cooling to room temperature at a rate of 10℃ / min.

[0046] It can be observed that no boundary line appears on the sidewall of the chip after curing, and there is no phenomenon of organic matter carrying silver particles climbing. Moreover, the shear strength of the chip after curing is 112.3N>100N, and the product is qualified.

[0047] Application Example 5 A chip mounting method, following the method in Application Example 4, differs in that... In the die bonding step: the chip size to be bonded is 2.23*4.02mm, and the chip area is 9.0mm². 2 , The specific steps involved in attaching the film are as follows: S1: Dispensing adhesive. Dispensing adhesive onto the tube shell substrate. Dispensing parameters are: dispensing air pressure 0.4MPa, dispensing time 15ms. S2: Let stand, place the tube shell substrate after dispensing glue for 310 seconds; S3: Bonding, bonding the chip with a chip size of 2.23*4.02mm to the shell substrate after S2 treatment to obtain the chip product; Then, the chip was cured according to the method in Application Example 4. After curing, no boundary line appeared on the sidewall of the chip, and there was no phenomenon of organic matter carrying silver particles climbing. Moreover, the shear strength of the chip after curing was 108.6N>100N, and the product was qualified.

[0048] Comparative Application Examples Comparative Application Example 1 A chip mounting method, following the method in Application Example 1, differs in that: In the curing step, the chip product after bonding is subjected to a heating stage, a isothermal stage and a cooling stage in sequence. The heating stage parameters are: heating from room temperature to 280°C at a heating rate of 15°C / min, holding for 5min, and then performing the isothermal stage and the cooling stage, which are carried out according to Application Example 1.

[0049] Comparative Application Example 2 A chip mounting method, following the method in Application Example 1, differs in that: In the curing process, the bonded chip products undergo a heating stage, a isothermal stage, and a cooling stage sequentially. The parameters for the heating stage are as follows: First stage: Heat from room temperature to 200℃ at a rate of 15℃ / min, and hold for 5min; Second stage: Heat to 280℃ at a rate of 30℃ / min, hold for 5min; Then, the isothermal and cooling phases are performed, following the procedures in Application Example 1.

[0050] No boundary lines were observed on the sidewalls of the cured chip products in Comparative Application Example 1 and Comparative Application Example 2. The shear strength of the cured chip products in Comparative Application Example 1 was 72.3 N, which did not meet the requirements; the shear strength of the chip in Comparative Application Example 2 was 105.8 N, which met the requirements. However, delamination and cracking of the conductive adhesive were observed in both Comparative Application Example 1 and Comparative Application Example 2, resulting in unsatisfactory appearance.

[0051] In summary, if bonding occurs immediately after applying adhesive during chip bonding, the conductive adhesive will separate from the chip sidewall, forming a boundary line. This phenomenon is caused by organic matter carrying silver particles upwards. When the product is subjected to mechanical or thermal stress during subsequent screening, the excess silver particles will fall off, causing abnormal electrical performance or failure of the product. Therefore, chips with boundary lines on their sidewalls are considered unqualified products.

[0052] In this application, through experimentation, it was found that if the settling time after dispensing and before bonding is too short, the result is similar to bonding immediately after dispensing, and a boundary line will still appear. However, if the settling time is too long, the shear strength of the chip, that is, the chemical bonding force with the substrate, is too weak and does not meet the requirements. Therefore, it was found through experimentation that the above situation will not occur when the settling time after dispensing and before bonding is appropriate, and the final product meets the requirements.

[0053] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A bonding process for silver conductive adhesive, characterized in that, Includes the following steps: S1: Dispensing adhesive, dispensing adhesive onto the surface of the substrate; S2: Settling, place the substrate after dispensing for a time of T; S3: Bonding, bonding the chip to the substrate after it has been left to stand, thus achieving chip bonding to the substrate; In step S2, the substrate placement time T is determined by the following method: After applying adhesive to the substrate surface, the chips were left for different durations. Then, chips of different sizes were adhered to the substrate surface and cured under the same conditions. The placement time T corresponding to the performance of different chip areas after curing was statistically analyzed. The performance was considered acceptable when no conductive adhesive boundary line appeared on the chip sidewall, i.e., no boundary line formed by the conductive adhesive climbing and carrying silver particles was observed on the chip sidewall, and the chip shear strength was >100N.

2. The bonding process of the silver conductive adhesive according to claim 1, characterized in that: The chip area is ≥1.0 mm². 2 And <3.0mm 2 At that time, the placement time T between dispensing and bonding is 180±10s; The chip area is ≥3.0mm². 2 and <5.0mm 2 At that time, the placement time T between dispensing adhesive and bonding is 250±10s; The chip area is ≥5.0mm². 2 And ≤10.0mm 2 The placement time T between dispensing the adhesive and bonding is 300±10s.

3. The bonding process of the silver conductive adhesive according to claim 1, characterized in that: The chip area is 1.8 mm. 2 At that time, the placement time T between dispensing and bonding is 180s; The chip area is 4.6 mm. 2 At that time, the placement time T between dispensing adhesive and bonding is 250s; The chip area is 5.4 mm. 2 At that time, the placement time T between dispensing the adhesive and bonding is 300s.

4. The bonding process of the silver conductive adhesive according to claim 1, characterized in that: The dispensing parameters in step S1 are as follows: dispensing air pressure is 0.4±0.05MPa, and dispensing time is 14-15ms.

5. A chip mounting method, characterized in that: Includes the following steps: Gluing: The chip and the substrate are bonded according to the glue bonding process of silver conductive adhesive as described in any one of claims 1-4; Curing: After curing by heating, cool to room temperature.

6. A chip mounting method according to claim 5, characterized in that: The heating process in the curing step includes a stepped heating stage and a constant temperature stage performed sequentially. The specific parameters of the stepped heating stage are as follows: First stage: Heat to 120±10℃ and hold for 3-5 minutes; Second stage: Heat to 200±10℃ and hold for 3-5 minutes; Third stage: Raise the temperature to 280±10℃ and hold for 3-5 minutes; The parameters for the isothermal stage are: heat up to 410-430℃ and hold for 8-12 minutes.

7. A chip mounting method according to claim 6, characterized in that: The heating rate in the first stage is 10-15℃ / min; The heating rate in the second stage is 20-25℃ / min; The heating rate in the third stage is 30-35℃ / min; The heating rate during the isothermal phase is 15-20℃ / min.

8. A chip mounting method according to claim 5, characterized in that: During the curing step, the cooling rate is 6-10℃ / min.

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