A method and system for quantifying solder flow loss of BGA solder balls

Abstract

The application provides a BGA solder ball solder loss rate quantification method and system, and relates to the technical field of microelectronic packaging, which comprises the following steps: obtaining the forming geometric parameters of finished BGA solder balls and calculating the original solder amount; obtaining the actual forming geometric parameters of the BGA solder balls after reflow soldering, and calculating the effective solder amount participating in ball forming after soldering; obtaining the solder loss rate according to the difference between the original solder amount and the effective solder amount participating in ball forming after soldering, comparing the solder loss rate with the loss rate threshold value, if the solder loss rate is greater than the threshold value, it is determined that the solder amount management is out of control, and the solder loss position is determined, if the solder loss rate is not greater than the threshold value, it is determined that the management is not out of control; setting a solder resist film for the determined loss position to block the solder loss path, and recalculating the solder loss rate after setting; when the solder loss rate is within the loss rate threshold value, the post-soldering shape geometric parameters are predicted according to the designed solder amount, and the actual forming result is compared and verified, and when the two are consistent, it is confirmed that the quantification method is effective.

Description

Technical Field

[0001] This invention relates to the field of microelectronic packaging technology, and in particular to a method and system for quantifying the solder loss rate of BGA solder balls. Background Technology

[0002] As 5G communication, artificial intelligence, autonomous driving, and consumer electronics evolve towards miniaturization and high performance, microelectronic packaging technology places higher demands on device interconnect density, heat dissipation performance, and packaging reliability. Compared to traditional packaging, BGA packaging offers higher pin density, superior heat dissipation, and stronger resistance to mechanical stress, and has been widely used in the miniaturization and integration of high-end electronic devices. In BGA packaging structures, the quality of the solder balls directly affects the electrical connection performance and reliability of the package structure. Solder ball height and coplanarity are important indicators for evaluating BGA solder ball quality.

[0003] In conventional BGA solder ball forming processes, the solder ball height and coplanarity are typically adjusted by controlling the solder quantity, solder paste printing parameters, and reflow soldering process parameters. For assessing the post-soldering solder ball condition, current technologies generally employ CT scanning or metallographic analysis to observe the internal or cross-sectional state of the solder ball, or use finite element simulation to predict the solder ball morphology. These methods can, to some extent, assist in judging the solder ball forming results and provide a reference for adjusting process parameters.

[0004] However, existing technologies lack quantitative characterization methods for BGA solder ball loss, resulting in an unknown black box range between the initial solder input and the effective solder ball formation after soldering. This makes it impossible to accurately grasp the actual solder loss during reflow soldering. At the same time, when the solder ball height is abnormal or the coplanarity is out of tolerance, existing technologies cannot determine whether the abnormality is due to solder ball forming problems or excessive solder loss, which can easily lead to incorrect process handling and further exacerbate problems such as uncontrolled solder ball shape, poor coplanarity, and cold solder joints. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method and system for quantifying the solder loss rate of BGA solder balls. This method can solve the problem that the prior art lacks quantitative characterization means for the amount of solder loss in BGA solder balls. There is an unknown black box range between the original amount of solder input and the amount of effective solder ball formed after soldering, making it impossible to accurately grasp the actual loss of solder during reflow soldering. At the same time, when the solder ball height is abnormal or the coplanarity is out of tolerance, the prior art has difficulty in determining whether the abnormality is due to solder ball forming problems or excessive solder loss, which can easily lead to incorrect process handling and further aggravate the technical problems of uncontrolled solder ball shape, poor coplanarity, and cold solder joints.

[0006] A first aspect of this invention provides a method for quantifying the solder loss rate of BGA solder balls, comprising: S1: Obtain the forming geometry parameters of the finished BGA solder balls and calculate the original solder amount; S2: Obtain the actual forming geometry parameters of the BGA solder balls after reflow soldering, and calculate the effective solder amount for ball formation after soldering; S3: Calculate the solder loss rate of BGA solder balls based on the original solder amount and the effective solder ball amount after soldering; S4: Determine whether the solder loss rate is greater than the loss rate threshold; if so, determine that the BGA solder ball has solder quantity management out of control and proceed to S5; otherwise, determine that the BGA solder ball does not have solder quantity management out of control. S5: Determine the location of solder loss based on the solder quantity management judgment results; S6: Apply a solder mask at the solder loss location to block the solder loss path, and recalculate the solder loss rate of the BGA solder ball after applying the solder mask; S7: Under the condition that the solder loss rate is within the loss rate threshold, predict the post-soldering geometric parameters of the BGA solder ball based on the designed solder amount; S8: Compare and verify the predicted BGA solder ball shape geometry parameters with the actual forming results. If the predicted post-soldering shape geometry parameters match the actual forming results, the quantitative method for BGA solder ball solder loss rate is determined to be effective.

[0007] A second aspect of the present invention provides a system for quantifying the solder loss rate of BGA solder balls, comprising: a processor and a memory; The memory stores programs or instructions that can run on the processor, which, when executed by the processor, implement the steps of a method for quantifying the solder loss rate of BGA solder balls as described in the first aspect.

[0008] A third aspect of the present invention provides a readable storage medium storing a program or instructions that, when executed by a processor, implement the steps of the method for quantifying the solder loss rate of BGA solder balls as described in the first aspect.

[0009] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: In this embodiment of the invention, by calculating the original solder amount before reflow soldering and the effective solder amount after reflow soldering for BGA solder balls, and further calculating the solder loss rate between the two, a quantitative characterization of the solder loss of BGA solder balls is achieved. This transforms the previously unknown black box interval between the original solder input and the effective solder amount after reflow soldering into a calculable and quantifiable indicator, thereby accurately grasping the actual solder loss during the reflow soldering process. Simultaneously, by comparing the solder loss rate with a loss rate threshold, and combining this with the determination of the solder loss location and the setting of the solder mask, incorrect process handling measures due to misjudgment caused by abnormalities can be avoided. Furthermore, under the condition that the solder loss rate is within the loss rate threshold, the post-soldering geometric parameters of the BGA solder balls are predicted based on the designed solder amount, and compared with the actual forming results for verification. This verifies the effectiveness of the quantification method for solder loss rate, thereby improving the accuracy of BGA solder ball solder quantity management, the stability of solder ball shape control, and the product welding reliability, and reducing the risk of defects such as uncontrolled solder ball shape, poor coplanarity, and cold solder joints. Attached Figure Description

[0010] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0011] Figure 1 This is a flowchart illustrating a method for quantifying the solder loss rate of BGA solder balls provided in an embodiment of the present invention.

[0012] Figure 2 This is a photograph of a solder ball forming with a 20% loss rate after welding, provided in an embodiment of the present invention.

[0013] Figure 3 This is a photograph of solder ball formation where the solder loss after soldering is within the loss rate threshold, provided by an embodiment of the present invention.

[0014] Figure 4 This is a schematic diagram of a BGA solder ball solder loss quantification system provided in an embodiment of the present invention. Detailed Implementation

[0015] To enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0016] The following description, in conjunction with the accompanying drawings, details a method for quantifying the solder loss rate of BGA solder balls provided by the present invention through specific embodiments and application scenarios.

[0017] Example 1 Reference manual attached Figure 1 The diagram shows a flowchart of a method for quantifying the solder loss rate of BGA solder balls according to an embodiment of the present invention.

[0018] This invention provides a method for quantifying the solder loss rate of BGA solder balls, which may include the following steps: S1: Obtain the forming geometry parameters of the finished BGA solder balls and calculate the original solder amount.

[0019] The initial solder amount refers to the total amount of solder present in the finished BGA solder balls before reflow soldering, and can be used as a benchmark value for subsequent calculations of solder loss and solder loss rate. In this scheme, the initial solder amount is obtained by referring to the solder ball radius provided by the manufacturer, combining the initial ball diameter of multiple finished BGA solder ball samples, and calculating the average ball diameter. Then, this average ball diameter is substituted into the ball volume calculation formula to obtain the total volume of the solder ball.

[0020] It should be noted that since BGA solder balls before reflow soldering are usually spherical or nearly spherical, this total volume can be used as the initial amount of solder ball before soldering, i.e., the original amount of solder, to be compared with the effective amount of solder ball after reflow soldering, thereby quantitatively characterizing the loss of solder during the soldering process.

[0021] In one possible implementation, S1 specifically includes: S101: Select multiple finished BGA solder ball samples and measure the initial ball diameter of each solder ball.

[0022] S102: Calculate the average diameter of the balls based on the initial diameters.

[0023] S103: Based on the average ball diameter, determine the total volume of the solder balls as the initial solder quantity using the solder ball volume calculation formula.

[0024] In this embodiment of the invention, through the above-described S1 step, this solution can accurately obtain the original solder amount of the finished BGA solder balls before reflow soldering, providing unified and reliable benchmark data for the subsequent calculation of solder loss amount and solder loss rate.

[0025] S2: Obtain the actual forming geometry parameters of the BGA solder balls after reflow soldering, and calculate the effective solder amount for ball formation after soldering.

[0026] Among them, the effective solder ball volume after soldering refers to the amount of solder that actually participates in the solder ball formation and remains on the solder pad after the finished BGA solder ball has been reflowed. It can be used to characterize the effective remaining solder volume of the solder ball after soldering is completed.

[0027] It should be noted that the volume of the BGA solder ball after soldering can be calculated by substituting the bottom radius of the ball and the height of the ball into the formula for calculating the ball volume. Since this ball volume reflects the actual volume of the solder ball body formed after reflow soldering, it can be used as the effective amount of solder balling after soldering and compared with the original amount of solder before reflow soldering, thus providing a basis for subsequent calculations of solder loss and solder loss rate.

[0028] In one possible implementation, S2 specifically includes: S201: Obtain morphological data of the BGA solder ball sample after reflow soldering to obtain the three-dimensional morphological data or cross-sectional morphological data of the BGA solder ball after soldering.

[0029] Among them, three-dimensional morphological data refers to data obtained through CT scans that reflect the overall spatial morphology of BGA solder balls after reflow soldering. This data typically includes the geometric information of the solder balls in the X, Y, and Z directions, and can comprehensively characterize the outer contour of the solder balls, the height of the crown, the bottom contact area, and the forming state between the solder balls and the pads.

[0030] Among them, cross-sectional morphology data refers to data obtained through CT scan cross-sectional images, metallographic cross-sectional images or other cross-sectional imaging methods that can reflect the forming contour of BGA solder balls in a specific cross-sectional direction after reflow soldering.

[0031] Specifically, the solder ball samples after reflow soldering are CT scanned to obtain cross-sectional views in the X, Y, and Z directions.

[0032] S202: Measure the bottom radius and height of the BGA solder ball's cap at the contact surface with the pad after soldering, based on the three-dimensional or cross-sectional shape.

[0033] Specifically, the contact radius between multiple solder balls and the pads and the height of the solder balls are measured on a cross-sectional view to obtain the average height of the solder ball crown. h and the bottom radius of the welding ball crown a .

[0034] S203: Calculate the volume of the BGA solder ball after soldering based on the bottom radius and height of the ball cap, and use it as the effective amount of solder for ball formation after soldering.

[0035] Optionally, the formula for calculating the volume of a spherical cap is as follows:

[0036] in, Indicates the amount of solder that effectively forms a ball after soldering. h This indicates the height of the BGA solder ball cap after reflow soldering. a This indicates the bottom radius of the BGA solder ball's crown after reflow soldering.

[0037] In this embodiment of the invention, through the above-described S2 step, this solution can accurately obtain key geometric parameters such as the bottom radius and height of the ball cap based on the actual morphology of the BGA solder ball after reflow soldering, and further calculate the effective solder amount for ball formation after soldering. Since this effective solder amount for ball formation directly reflects the volume of solder actually retained and participating in the formation of the solder ball after reflow soldering, it can form a quantitative comparison with the original solder amount before reflow soldering, avoiding subjective judgment based solely on abnormal appearance or height of the solder ball.

[0038] S3: Calculate the solder loss rate of BGA solder balls based on the original solder amount and the effective solder ball amount after soldering.

[0039] Solder loss rate refers to the proportion of BGA solder balls that fail to remain on the pads and participate in effective ball formation during reflow soldering, relative to the original amount of solder before reflow soldering. It is used to quantitatively characterize the degree of solder loss during the soldering process.

[0040] In one possible implementation, S3 specifically includes: S301: Calculate the solder loss based on the original solder amount and the effective ball solder amount after soldering.

[0041] Optionally, the solder loss can be calculated as follows:

[0042] in, Indicates the amount of solder lost. This indicates the total volume of the solder balls calculated based on their diameter before reflow soldering.

[0043] S302: The ratio of solder loss to the original amount of solder is used as the solder loss rate of BGA solder balls.

[0044] Optionally, the solder loss rate can be calculated as follows:

[0045] in, This indicates the solder loss rate.

[0046] In this embodiment of the invention, through the above-described S3 step, this solution can accurately calculate the solder loss amount and solder loss rate of BGA solder balls during the reflow soldering process based on the original solder amount before reflow soldering and the effective ball-forming solder amount after reflow soldering. This transforms solder loss, a process phenomenon that is difficult to judge directly, into a quantifiable and comparable numerical indicator. Since the solder loss rate uses the original solder amount as a unified benchmark, it can objectively reflect the degree of solder loss under different solder ball samples or different process conditions. Therefore, it is beneficial to determine whether problems such as abnormal solder ball height or coplanarity are caused by solder loss, avoiding misjudgments based solely on appearance or experience.

[0047] S4: Determine if the solder loss rate exceeds the loss rate threshold. If yes, determine that there is a loss of control over solder quantity management in the BGA solder balls and proceed to S5. Otherwise, determine that there is no loss of control over solder quantity management in the BGA solder balls.

[0048] It should be noted that those skilled in the art can set the churn rate threshold according to actual needs, and this invention does not limit that.

[0049] S5: Determine the location of solder loss based on the solder quantity management judgment results.

[0050] Solder loss location refers to the specific location where, during the reflow soldering process of BGA solder balls, solder fails to remain on the pads and solder ball forming area, but migrates, penetrates, or remains along structural gaps, unintended wetting areas, or capillary channels, thus failing to be retained. This location is typically related to the pad side structure, the assembly gap between the inner conductor and the insulator, the surface condition of non-soldering areas, and the solder wetting path.

[0051] In one possible implementation, S5 specifically includes: In cases where solder quantity management is deemed out of control, the location of solder loss can be determined through CT scanning or metallographic analysis.

[0052] S6: Apply solder mask at the solder loss location to block the solder loss path and recalculate the solder loss rate of BGA solder balls after applying the solder mask.

[0053] In one possible implementation, S6 specifically includes: S601: Apply a fixed thickness of green solder mask evenly to the solder loss location, wherein the area covered by the green solder mask is the non-soldering area of ​​the inner conductor.

[0054] S602: Control the green solder mask thickness above the critical value that blocks solder flow, and bake the film after applying the green solder mask according to the manufacturer's recommended process parameters.

[0055] S603: After setting the solder mask, recalculate the solder loss rate of the BGA solder balls to obtain the solder loss rate.

[0056] Optionally, it also includes confirming whether the solder resist film effectively blocks solder loss based on whether the solder loss rate is within the loss rate threshold range.

[0057] In this embodiment of the invention, through the above-described S6 step, the solution can set a solder resist film (such as uniformly coating green solder mask in the non-soldering area of ​​the inner conductor) at the solder loss location, effectively blocking the solder loss along an unexpected path, thereby reducing the solder loss rate to within the loss rate threshold. By controlling the green solder mask thickness above the critical value for blocking solder flow and baking according to the recommended process parameters, the solder resist measures can be ensured to be reliable and repeatable, providing a stable prerequisite for subsequent solder ball shape prediction, making solder quantity management controllable, and improving the molding quality and process reliability of BGA packaging.

[0058] S7: Under the condition that the solder loss rate is within the loss rate threshold, predict the post-soldering geometric parameters of BGA solder balls based on the designed solder amount.

[0059] It's important to note that only when solder loss is minimal and largely prevented from occurring unexpectedly can the designed solder amount before reflow soldering be approximately equivalent to the effective solder amount actually used for ball formation after soldering. In this case, the solder ball height, crown shape, and contact angle are primarily determined by the solder input, pad size, wetting state, and surface tension, providing a stable basis for the calculation model's predictions. If the solder loss rate is high, the post-solder ball morphology is affected not only by the designed solder amount but also by random loss, loss paths, and loss locations, making it impossible to accurately determine whether the solder ball height variation originates from design parameters or solder loss. Therefore, controlling the solder loss rate within a threshold value eliminates this major uncertainty, making the predicted solder ball shape closer to the actual formed result.

[0060] In one possible implementation, S7 specifically includes: S701: Calculate the first total volume of the sphere after soldering based on the designed solder amount, provided that the solder loss rate is within the loss rate threshold.

[0061] Optionally, the churn rate threshold is generally between 2% and 3%.

[0062] S702: Calculate the second total volume of the sphere after welding based on a preset void ratio of 5%.

[0063] Optionally, the second total volume is calculated as follows:

[0064] in, This indicates the second total volume.

[0065] S703: Calculate the height of the spherical crown based on the second total volume and the radius of the bottom circle of the spherical crown.

[0066] Alternatively, the formula for calculating the height of the spherical crown is:

[0067] in, h Indicates the height of the BGA solder ball crown. V This indicates the total volume of the sphere after welding. a This indicates the radius of the bottom of the BGA solder ball's crown.

[0068] S704: Substitute the radius of the bottom circle of the sphere and the height of the sphere into the contact angle calculation formula to obtain the contact angle.

[0069] Optionally, the contact angle calculation formula is as follows:

[0070] in, Indicates contact angle θ The tangent value, θ Indicates the contact angle of the BGA solder ball. j The first height component represents the height of the BGA solder ball crown. k The second height component represents the height of the BGA solder ball crown.

[0071] S705: Use the crown height and contact angle as the predicted post-soldering geometry parameters of the BGA solder ball.

[0072] In this embodiment of the invention, through the above-described S7 step, the solution can predict the post-soldering geometric parameters of BGA solder balls based on the designed solder amount under the condition that the solder loss rate is stable within the loss rate threshold, thereby avoiding interference from random solder loss on the calculation results. This step can determine in advance whether the solder ball height, protrusion state, and wetting morphology meet the design requirements before actual soldering or during the process optimization stage, reducing the number of repeated experiments and process adjustments, and providing a theoretical basis for solder ball height control, coplanarity improvement, and BGA soldering reliability enhancement.

[0073] S8: Compare and verify the predicted BGA solder ball shape geometry parameters with the actual forming results. If the predicted post-soldering shape geometry parameters match the actual forming results, the quantitative method for BGA solder ball solder loss rate is confirmed to be effective.

[0074] In one possible implementation, S8 specifically includes: S801: Measure the crown height and contact angle of the BGA solder ball after soldering.

[0075] S802: When the measured height and contact angle of the ball match the calculated height and contact angle of the ball, the method for quantifying the solder loss rate of BGA solder balls is deemed effective.

[0076] In this embodiment of the invention, the proposed solution can compare and verify the predicted geometric parameters of the BGA solder ball shape with the actual solder ball forming results after reflow soldering, thereby verifying the accuracy and reliability of the method for quantifying solder loss rate. When the measured solder ball crown height and contact angle match the calculated predicted values, it indicates that the method can accurately reflect the actual solder loss during the reflow soldering process and effectively predict the solder ball forming shape. This step not only verifies the feasibility of the calculation model and measurement method but also provides an objective basis for solder ball forming quality control, process optimization, and solder quantity management, making the improvement of solder ball height consistency and coplanarity a quantifiable engineering reference.

[0077] Example 2 Reference manual attached Figure 2 The image shows a photograph of a solder ball forming process with a 20% loss rate after soldering, provided by an embodiment of the present invention.

[0078] Reference manual attached Figure 3 The image shows a solder ball formation photograph provided by an embodiment of the present invention, in which the solder loss after soldering is within the loss rate threshold.

[0079] Step 1: Calculate the amount of solder for the solder balls: Step 101: Test the diameter of multiple solder balls and obtain the average ball diameter R = 0.4 mm.

[0080] Step 102: According to the formula for the total volume of solder balls, we obtain... .

[0081] Step 2: Total volume of solder balls after soldering when solder loss is within the loss rate threshold.

[0082] Step 201: If the void ratio of the solder ball is set to 5%, then the volume of the solder ball after welding can be obtained. ,but .

[0083] Step 3: Calculate the height and radius of curvature of the spherical cap: Step 301: Given that the pad diameter is 0.4 mm, the bottom radius of the spherical cap is a = 0.2 mm.

[0084] Step 302, Substituting a=0.2mm into the formula for calculating the height of the spherical crown, we get the height of the spherical crown h=0.311mm.

[0085] Step 303: Substitute the known data into the contact angle calculation formula to obtain... θ ≈114.5°.

[0086] Step 4, Solder ball shape prediction: Step 401: The contact angle is 114.5°. Since 114.5° > 90°, the spherical crown is raised, indicating that wetting is dominant in the wetting process of solder and pad within 0.4mm, while surface tension is dominant rather than wetting outside 0.4mm, which indirectly confirms that there is no solder loss.

[0087] Step 402: The formed solder ball is a raised spherical crown with a bottom diameter of 0.4 mm and a height of 0.311 mm.

[0088] Reference manual attached Figure 4 The diagram shows a structural schematic of a BGA solder ball solder loss quantification system provided in an embodiment of the present invention.

[0089] This invention provides a BGA solder ball solder loss rate quantification system 20, including: a processor 201 and a memory 202; The memory 202 stores programs or instructions that can run on the processor 201. When the program or instructions are executed by the processor 201, they implement the steps of the above-described method for quantifying the solder loss rate of BGA solder balls and achieve the same technical effect. To avoid repetition, the present invention will not elaborate further.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do 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. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the protection scope of the present invention.

Claims

1. A method for quantifying the solder loss rate of BGA solder balls, characterized in that, include: S1: Obtain the forming geometry parameters of the finished BGA solder balls and calculate the original solder amount; S2: Obtain the actual forming geometry parameters of the BGA solder balls after reflow soldering, and calculate the effective solder amount for ball formation after soldering; S3: Calculate the solder loss rate of BGA solder balls based on the original solder amount and the effective solder ball amount after soldering; S4: Determine whether the solder loss rate is greater than the loss rate threshold; If so, it is determined that the BGA solder ball has a solder quantity management failure, and proceeds to S5; Otherwise, it is determined that there is no loss of control over the solder quantity management of the BGA solder balls; S5: Determine the location of solder loss based on the solder quantity management judgment results; S6: Apply a solder mask at the solder loss location to block the solder loss path, and recalculate the solder loss rate of the BGA solder ball after applying the solder mask; S7: Under the condition that the solder loss rate is within the loss rate threshold, predict the post-soldering geometric parameters of the BGA solder ball based on the designed solder amount; S8: Compare and verify the predicted BGA solder ball shape geometry parameters with the actual forming results. If the predicted post-soldering shape geometry parameters match the actual forming results, the quantitative method for BGA solder ball solder loss rate is determined to be effective.

2. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, S1 specifically includes: S101: Select multiple finished BGA solder ball samples and measure the initial ball diameter of each solder ball; S102: Calculate the average ball diameter based on each of the initial ball diameters; S103: Based on the average ball diameter, the total volume of the solder balls is determined as the original solder quantity using the solder ball volume calculation formula.

3. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, S2 specifically includes: S201: Obtain morphological data of BGA solder ball samples after reflow soldering to obtain the three-dimensional or cross-sectional shape of the BGA solder ball after soldering. S202: Based on the aforementioned three-dimensional or cross-sectional shape, measure the bottom radius and height of the ball crown at the contact surface between the BGA solder ball and the pad after soldering; S203: Calculate the volume of the BGA solder ball after soldering based on the bottom radius and height of the ball cap, and use it as the effective amount of solder for ball formation after soldering.

4. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, Specifically, S3 includes: S301: Calculate the solder loss based on the original solder amount and the effective ball-forming solder amount after soldering; S302: The ratio of the solder loss amount to the original solder amount is taken as the solder loss rate of the BGA solder ball.

5. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, Specifically, S5 is: In cases where solder quantity management is deemed out of control, the location of solder loss can be determined through CT scanning or metallographic analysis.

6. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, S6 specifically includes: S601: A fixed thickness of green oil is uniformly applied to the location where the solder has leaked, wherein the area covered by the green oil is the non-soldering area of ​​the inner conductor; S602: Control the thickness of the green solder mask to be above the critical value that blocks the flow of solder, and bake the film layer after coating with green solder mask according to the process parameters recommended by the manufacturer. S603: After applying the solder mask, recalculate the solder loss rate of the BGA solder balls to obtain the solder loss rate.

7. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, Specifically, S7 includes: S701: Calculate the first total volume of the sphere after soldering based on the designed amount of solder, provided that the solder loss rate is within the loss rate threshold. S702: Calculate the second total volume of the sphere after welding based on a preset void ratio of 5%; S703: Calculate the height of the spherical cap based on the second total volume and the radius of the bottom circle of the spherical cap; S704: Substitute the radius of the bottom circle of the sphere and the height of the sphere into the contact angle calculation formula to obtain the contact angle; S705: Use the height of the ball cap and the contact angle as the predicted post-soldering geometric parameters of the BGA solder ball.

8. The method for quantifying the solder loss rate of BGA solder balls according to claim 1, characterized in that, S8 specifically includes: S801: Measure the crown height and contact angle of the BGA solder ball after soldering; S802: If the measured height and contact angle of the ball match the calculated height and contact angle of the ball, the method for quantifying the solder loss rate of the BGA solder ball is deemed effective.

9. A system for quantifying the solder loss rate of BGA solder balls, characterized in that, include: Processor and memory; The memory stores programs or instructions that can run on the processor, which, when executed by the processor, implement the steps of the method for quantifying the solder loss rate of BGA solder balls as described in any one of claims 1 to 8.

10. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the method for quantifying the solder loss rate of BGA solder balls as described in any one of claims 1 to 8.

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