Automatic detection system and method for quality of BGA (Ball Grid Array) packaged circuit

Abstract

The invention discloses an automatic detection system and method for BGA packaging circuit quality, and the method comprises the steps: randomly selecting X BGA packaging circuits from a qualified workshop as evaluation samples for thermal performance detection, and carrying out the detection and analysis of the thermal performance parameters of each evaluation sample, obtaining a thermal performance evaluation index of the BGA packaging circuit of the current production batch, and presetting three groups of index value ranges corresponding to the thermal performance evaluation index Gtr; and matching the thermal performance evaluation index of the BGA packaging circuit of the current production batch with the preset three groups of index value ranges, thereby obtaining the thermal performance grade of the BGA packaging circuit of the current production batch, and solving the problems that in the prior art, when quality detection is carried out on the BGA packaging circuit, evaluation on the thermal performance of the BGA packaging circuit is lacked, and the quality detection efficiency is poor. Therefore, the problem of quality detection singleness is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of packaged circuit quality detection, and in particular to an automated detection system and method for BGA packaged circuit quality. Background Art

[0002] With the development of electronic technology, BGA packaged circuits are widely used in electronic devices due to their high density and high performance. BGA packaging provides more I / O interfaces and better electrical performance, but it also brings higher quality and reliability requirements.

[0003] However, the BGA package circuit quality automatic detection in the prior art still has the following deficiencies:

[0004] Reliance on manual inspection results in low inspection efficiency and is easily affected by human factors, resulting in unstable inspection results. In addition, manual inspection is difficult to accurately identify tiny defects;

[0005] At the same time, when conducting quality inspection on BGA packaged circuits, there is a lack of evaluation on the thermal performance of BGA packaged circuits, resulting in the singleness of quality inspection.

[0006] To this end, an automated detection system and method for BGA package circuit quality are introduced. Summary of the invention

[0007] In view of this, the present invention provides an automated detection system and method for BGA package circuit quality to solve the problems raised by the above background technology.

[0008] The purpose of the present invention can be achieved by the following technical solution: An automated detection system for BGA package circuit quality, comprising:

[0009] Image acquisition module: Place the BGA package circuit on the detection position of the automated detection platform, collect image information of the BGA package circuit and send it to the defect assessment module;

[0010] Defect evaluation module: receives image information of BGA package circuit and analyzes it to obtain defect evaluation index Qer of BGA package circuit;

[0011] Quality sorting module: According to the defect evaluation index Qer of the BGA packaged circuit, the quality level of the BGA packaged circuit is determined and sent to the workshop of the corresponding quality level; the quality level includes qualified level, defective level and scrap level, and the corresponding workshops are qualified workshop, repair workshop and scrap workshop respectively;

[0012] Performance evaluation module: X BGA packaged circuits are randomly selected from the qualified workshop as evaluation samples for thermal performance testing, and the thermal performance parameters of each evaluation sample are tested and analyzed, thereby obtaining the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch. Based on the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, the thermal performance level of the BGA packaged circuit of the current production batch is obtained; the thermal performance parameters include thermal conductivity and thermal expansion coefficient;

[0013] Report generation module: fills the inspection data of the current production batch of BGA packaged circuits into the preset template to generate an inspection report for the current production batch of BGA packaged circuits; the inspection data includes the number of qualified workshops, the number of repair workshops, the number of scrapped workshops and the thermal performance level of the BGA packaged circuits.

[0014] In some embodiments, image information of a BGA packaged circuit is received and analyzed, specifically:

[0015] After receiving the image information of the BGA package circuit, the image information is converted into a grayscale image; the grayscale image is converted into a binary image so that the solder joint area is separated from the background; based on the grayscale value of each solder joint area, the grayscale mean and standard deviation are calculated;

[0016] A reference threshold range of gray values ​​is set, and the reference threshold range is the difference between the gray mean and two times the standard deviation to the sum of the dust mean and two times the standard deviation; based on the set reference threshold range, the solder joint areas with gray values ​​higher or lower than the set reference threshold range are marked as abnormal areas; the number of abnormal areas is counted and recorded as the number of abnormalities Ea; for each group of abnormal areas, the gray values ​​of each abnormal area are extracted, and corresponding calculations are performed based on the comparison results with the reference threshold range. If the gray values ​​of a group of abnormal areas are higher than the reference threshold range, the difference between the gray values ​​of the group of abnormal areas and the highest value in the reference threshold range is calculated; if the gray values ​​of a group of abnormal areas are lower than the reference threshold range, the difference between the gray values ​​of the group of abnormal areas and the lowest value in the reference threshold range is calculated, and the absolute value is taken;

[0017] The difference calculated for each group of abnormal areas is extracted, and the average is taken to obtain the abnormal mean value Eb; the number of pixels in each group of abnormal areas is calculated, and the number is accumulated to obtain the abnormal face value Ec.

[0018] In some embodiments, the defect evaluation index Qer of the BGA package circuit is obtained, specifically:

[0019] According to the formula The abnormal number Ea, abnormal mean Eb and abnormal face value Ec of the BGA packaged circuit are weightedly calculated to obtain the defect evaluation index Qer of the BGA packaged circuit; wherein Va, Vb, Vc represent the maximum allowable abnormal number, maximum allowable abnormal mean and maximum allowable abnormal face value Ec corresponding to the abnormal number Ea, abnormal mean Eb and abnormal face value Ec, respectively, and t1, t2 and t3 are the influencing weight factors of the abnormal number Ea, abnormal mean Eb and abnormal face value Ec, respectively.

[0020] In some embodiments, the quality level of the BGA packaged circuit is determined according to the defect evaluation index Qer of the BGA packaged circuit, and the BGA packaged circuit is transported to a workshop of the corresponding quality level, specifically:

[0021] Three groups of index value ranges of the preset defect assessment index Qer are set, and the three groups of index value ranges are set to correspond to the qualified grade, the defective grade and the scrap grade respectively; the defect assessment index Qer of the BGA packaged circuit is matched with the preset three groups of index value ranges, thereby obtaining the quality grade of the BGA packaged circuit; based on the quality grade of the BGA packaged circuit, the BGA packaged circuit is transported to a workshop of the corresponding quality grade.

[0022] In some embodiments, if the number of BGA packaged circuits delivered to a defective workshop exceeds the processing quantity threshold set corresponding to the workshop, an adjustment signal is triggered, and the BGA packaged circuits exceeding the processing quantity threshold are marked and delivered to a scrap workshop.

[0023] In some embodiments, the thermal performance parameters of each evaluation sample are detected and analyzed, specifically:

[0024] Apply heat to each BGA package circuit based on preset conditions; record the thermal conductivity value obtained by testing each BGA package circuit Y times; where Y>4; calculate the average value of each group of thermal conductivity values ​​obtained by testing each BGA package circuit, and use the calculated average values ​​of each group as the thermal conductivity average value Rd i of each BGA package circuit; where i represents the number of the extracted BGA package circuit, i=1,2...X;

[0025] At the same time, the highest value and the lowest value are extracted from each group of thermal conductivity values ​​obtained by testing each BGA package circuit, and are used as the thermal conductivity peak value Rci and the thermal conductivity valley value Rhi of each BGA package circuit respectively;

[0026] The minimum allowable value of the thermal conductivity value corresponding to the BGA package circuit is preset; the preset minimum allowable value is marked as Rpi;

[0027] Using the formula The thermal conductivity mean value Rd i, thermal conductivity peak value Rci and thermal conductivity valley value Rh i of each BGA package circuit are weightedly calculated to obtain the thermal conductivity performance value Rn i of each BGA package circuit; wherein u1, u2 and u3 are the influencing weight factors of the thermal conductivity mean value Rd i, thermal conductivity peak value Rci and thermal conductivity valley value Rh i, respectively.

[0028] In some embodiments, the thermal performance parameters of each evaluation sample are detected and analyzed, further comprising:

[0029] Heat each BGA package circuit based on preset conditions; during the heating process, record the size change data of each BGA package circuit at different set temperature points, and calculate the thermal expansion coefficient of each BGA package circuit at different set temperature points; construct an expansion change trend diagram of each BGA package circuit based on the thermal expansion coefficient of each BGA package circuit at different set temperature points;

[0030] Draw the numerical points corresponding to the thermal expansion coefficient of each BGA package circuit at different set temperature points in the expansion change trend diagram, and connect adjacent numerical points to obtain the coefficient line;

[0031] Calculate the slope of each coefficient line and the angle with the horizontal line. If the angle between a coefficient line and the horizontal line is an acute angle, mark the slope of the coefficient line as a descending slope. If the angle between a coefficient line and the horizontal line is an obtuse angle, mark the slope of the coefficient line as an ascending slope. Sum all the ascending slopes and descending slopes to obtain the total ascending value and the total descending value. Calculate the ratio of the total ascending value to the total descending value of each BGA package circuit, that is, calculate by the total ascending value / the total descending value, and use the calculated ratio as the expansion ratio Ms i of each BGA package circuit.

[0032] The average value of the thermal expansion coefficient of each BGA package circuit at different set temperature points is calculated, and the calculated average value is used as the expansion mean value Mhi of each BGA package circuit;

[0033] The maximum allowable expansion ratio and the maximum allowable expansion mean value corresponding to the BGA package circuit expansion ratio Ms i and the expansion mean value Mh i are respectively preset, and the maximum allowable expansion ratio and the maximum allowable expansion mean value are marked as Ls i and Lh i respectively;

[0034] According to the formula The expansion ratio Ms i and the expansion mean Mh i of each BGA package circuit are weightedly calculated to obtain the thermal expansion performance value Mq i of each BGA package circuit; wherein c1 and c2 are the influencing weight factors of the expansion ratio Ms i and the expansion mean Mh i, respectively.

[0035] In some embodiments, the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch is obtained, specifically:

[0036] Extract the thermal conductivity performance value Rn i and the thermal expansion performance value Mq i of each BGA package circuit, calculate the average value of the thermal conductivity performance value Rn i and the thermal expansion performance value Mq i of each BGA package circuit, and use the calculated average value as the thermal conductivity evaluation index and thermal expansion evaluation index of the BGA package circuit of the current production batch;

[0037] Based on the thermal conductivity evaluation index and thermal expansion evaluation index of the BGA packaged circuit of the current production batch, the index value ranges of each group corresponding to the thermal conductivity evaluation index and the thermal expansion evaluation index are preset respectively, and each group of index value ranges corresponding to the thermal conductivity evaluation index is set to correspond to a thermal conductivity score, and each group of index value ranges corresponding to the thermal expansion evaluation index is set to correspond to a thermal expansion score;

[0038] The thermal conductivity evaluation index and thermal expansion evaluation index of the BGA packaged circuit of the current production batch are matched with the corresponding preset index value ranges, thereby obtaining the thermal conductivity score and thermal expansion score of the BGA packaged circuit of the current production batch, and the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch is obtained by accumulating the thermal conductivity score and thermal expansion score.

[0039] In some embodiments, the thermal performance level of the BGA packaged circuit of the current production batch is obtained, specifically:

[0040] The three groups of index value ranges corresponding to the preset thermal performance evaluation index Gtr are set to correspond to a thermal performance level respectively, and the thermal performance levels include excellent level, good level and poor level; the thermal performance evaluation index Gtr of the current production batch of BGA packaged circuits is matched with the preset three groups of index value ranges, thereby obtaining the thermal performance level of the current production batch of BGA packaged circuits.

[0041] In some embodiments, an automated detection method for BGA package circuit quality includes:

[0042] S1: The BGA packaged circuit is placed on the detection position of the automated detection platform through the automated sorting equipment, and the image information of the BGA packaged circuit is collected and analyzed through the high-resolution camera to obtain the defect evaluation index Qer of the BGA packaged circuit;

[0043] S2: According to the defect evaluation index Qer of the BGA packaged circuit, the quality level of the BGA packaged circuit is determined and sent to the workshop of the corresponding quality level; the quality level includes qualified level, defective level and scrap level, and the corresponding workshops are qualified workshop, repair workshop and scrap workshop respectively;

[0044] S3: Randomly select X BGA packaged circuits from the qualified workshop as evaluation samples for thermal performance testing, and test and analyze the thermal performance parameters of each evaluation sample, thereby obtaining the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, and based on the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, obtain the thermal performance grade of the BGA packaged circuit of the current production batch; the thermal performance parameters include thermal conductivity and thermal expansion coefficient;

[0045] S4: Fill the inspection data of the current production batch of BGA packaged circuits into a preset template to generate an inspection report for the current production batch of BGA packaged circuits; the inspection data includes the number of qualified workshops, the number of repair workshops, the number of scrapped workshops and the thermal performance level of the BGA packaged circuits.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] The present invention reduces the subjectivity and fatigue of manual inspection through automated image analysis, improves inspection efficiency and consistency, and ensures the stability of the quality control process; by calculating the number of abnormalities, the average value of abnormalities, and the face value of abnormalities, quantitative indicators are provided to evaluate welding quality, making quality control more objective and traceable;

[0048] The present invention randomly selects X BGA packaged circuits from a qualified workshop as evaluation samples for thermal performance detection, and detects and analyzes the thermal performance parameters of each evaluation sample, thereby obtaining the thermal performance evaluation index of the BGA packaged circuit of the current production batch, and presetting three groups of index value ranges corresponding to the thermal performance evaluation index Gtr; the thermal performance evaluation index of the BGA packaged circuit of the current production batch is matched with the preset three groups of index value ranges, thereby obtaining the thermal performance level of the BGA packaged circuit of the current production batch, which solves the problem of lack of evaluation of the thermal performance of the BGA packaged circuit when performing quality detection on the BGA packaged circuit in the prior art, resulting in the singleness of quality detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Further details, features and advantages of the present application are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0050] Figure 1 It is a principle block diagram of the present invention;

[0051] Figure 2 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0052] Several embodiments of the present application will be described in more detail below with reference to the accompanying drawings so that those skilled in the art can implement the present application. The present application can be embodied in many different forms and purposes and should not be limited to the embodiments described herein. These embodiments are provided to make the present application comprehensive and complete, and to fully convey the scope of the present application to those skilled in the art. The embodiments do not limit the present application.

[0053] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which this application belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and / or this specification, and will not be interpreted in an idealized or overly formal sense, unless explicitly defined as such herein.

[0054] See also Figure 1 As shown, an automated inspection system for BGA package circuit quality includes an image acquisition module, a defect assessment module, a quality sorting module, a performance assessment module, and a report generation module;

[0055] The image acquisition module is used to place the BGA package circuit on the detection position of the automated detection platform through an automated sorting device; the automated sorting device is an automated robotic arm; the image information of the BGA package circuit is collected through a high-resolution camera and sent to the defect assessment module;

[0056] The images collected in this process will be affected by factors such as uneven illumination and noise, so they need to be preprocessed. The preprocessing steps may include grayscale, filtering and denoising, contrast enhancement, etc., to improve image quality and highlight defect features;

[0057] The defect evaluation module is used to receive image information of the BGA package circuit and analyze it, thereby obtaining a defect evaluation index Qer of the BGA package circuit;

[0058] Specifically:

[0059] After receiving the image information of the BGA package circuit, the image information is converted into a grayscale image;

[0060] Grayscale images can more intuitively reflect the reflective characteristics of the solder joint surface. The grayscale value can reflect the smoothness and consistency of the solder joint surface;

[0061] Select an appropriate threshold to convert the grayscale image into a binary image so that the solder joint area is separated from the background; the threshold can be automatically determined by the OTSU algorithm, or manually set according to the histogram of the image; based on the grayscale value of each solder joint area, the grayscale mean and standard deviation are calculated; the standard deviation is calculated by using the standard deviation formula for the grayscale value of each solder joint area;

[0062] Set the reference threshold range of gray value, the reference threshold range is the difference between gray mean and two times standard deviation to the sum of dust mean and two times standard deviation;

[0063] Based on a set reference threshold range, marking a solder joint area whose grayscale value is higher or lower than the set reference threshold range as an abnormal area;

[0064] Count the number of abnormal areas and record it as the number of abnormal areas Ea; for each group of abnormal areas, extract the grayscale value of each abnormal area, and perform corresponding calculations based on the comparison results with the reference threshold range. If the grayscale value of a group of abnormal areas is higher than the reference threshold range, calculate the difference between the grayscale value of the group of abnormal areas and the highest value in the reference threshold range; if the grayscale value of a group of abnormal areas is lower than the reference threshold range, calculate the difference between the grayscale value of the group of abnormal areas and the lowest value in the reference threshold range, and take the absolute value;

[0065] The difference calculated for each group of abnormal areas is extracted, and the average is taken to obtain the abnormal mean value Eb; the number of pixels in each group of abnormal areas is calculated, and the number of pixels is accumulated to obtain the abnormal face value Ec;

[0066] According to the formula The abnormal number Ea, abnormal mean value Eb and abnormal face value Ec of the BGA package circuit are weightedly calculated to obtain the defect evaluation index Qer of the BGA package circuit; wherein Va, Vb and Vc represent the maximum allowable abnormal number, maximum allowable abnormal mean value and maximum allowable abnormal face value Ec corresponding to the abnormal number Ea, abnormal mean value Eb and abnormal face value Ec, respectively, and are set by technical personnel according to the quality requirements of the BGA package circuit; t1, t2 and t3 are the influence weight factors of the abnormal number Ea, abnormal mean value Eb and abnormal face value Ec respectively;

[0067] It should be noted that automated image analysis reduces the subjectivity and fatigue of manual inspection, improves inspection efficiency and consistency, and ensures the stability of the quality control process; by calculating the number of anomalies, the average value of anomalies, and the face value of anomalies, it provides quantitative indicators to evaluate welding quality, making quality control more objective and traceable.

[0068] The quality sorting module is used to determine the quality level of the BGA packaged circuit according to the defect evaluation index Qer of the BGA packaged circuit, and transport it to the workshop of the corresponding quality level; the quality level includes qualified level, defective level and scrap level, and the corresponding workshops are qualified workshop, repair workshop and scrap workshop respectively;

[0069] Specifically:

[0070] Preset three groups of index value ranges of the defect evaluation index Qer, and set the three groups of index value ranges to correspond to the qualified grade, the defective grade, and the scrap grade respectively; match the defect evaluation index Qer of the BGA package circuit with the preset three groups of index value ranges, thereby obtaining the quality grade of the BGA package circuit;

[0071] Based on the quality level of the BGA packaged circuit, the BGA packaged circuit is transported to the workshop of the corresponding quality level. If the number of BGA packaged circuits transported to the defective workshop during this process exceeds the processing quantity threshold set for the workshop, the adjustment signaling is triggered, and the BGA packaged circuits exceeding the processing quantity threshold are marked and transported to the scrap workshop;

[0072] It should be noted that the quality grading of BGA packaged circuits through an automated system improves the efficiency and accuracy of grading, reduces errors and inconsistencies in manual operations, and by setting a processing quantity threshold, it can prevent the repair workshop from operating overloaded.

[0073] The performance evaluation module is used to randomly select X BGA packaged circuits from the qualified workshop as evaluation samples for thermal performance detection, and detect and analyze the thermal performance parameters of each evaluation sample, thereby obtaining the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, and based on the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, obtaining the thermal performance grade of the BGA packaged circuit of the current production batch; the thermal performance parameters include thermal conductivity and thermal expansion coefficient;

[0074] Specifically:

[0075] Place the extracted X BGA package circuits on the thermal conductivity test equipment, and apply heat to each BGA package circuit based on preset conditions; the preset conditions are the test heat range applied, and the heat can be continuous or pulsed to simulate the heat load under actual working conditions;

[0076] Record the thermal conductivity values ​​obtained from the tests of each BGA package circuit Y times; where Y>4, and the specific value of Y is set according to the type of BGA package and the test conditions;

[0077] The average values ​​of the thermal conductivity values ​​of each group obtained by testing each BGA package circuit are calculated respectively, and the average values ​​of each group are used as the thermal conductivity average value Rd i of each BGA package circuit; wherein i represents the number of the extracted BGA package circuit, i=1,2...X;

[0078] At the same time, the highest value and the lowest value are extracted from each group of thermal conductivity values ​​obtained by testing each BGA package circuit, and are used as the thermal conductivity peak value Rci and the thermal conductivity valley value Rhi of each BGA package circuit respectively;

[0079] The minimum allowable value of the thermal conductivity value corresponding to the BGA package circuit is preset; it is set according to the material characteristics, design requirements and application environment of the BGA package circuit; the preset minimum allowable value is marked as Rpi;

[0080] Using the formula The thermal conductivity mean value Rd i, the thermal conductivity peak value Rci and the thermal conductivity valley value Rh i of each BGA package circuit are weightedly calculated to obtain the thermal conductivity performance value Rn i of each BGA package circuit; wherein u1, u2 and u3 are the influence weight factors of the thermal conductivity mean value Rd i, the thermal conductivity peak value Rci and the thermal conductivity valley value Rh i respectively;

[0081] It should be noted that by quantitatively evaluating the thermal performance of BGA packaged circuits, their reliability in practical applications can be ensured, especially in environments with high temperatures or temperature changes; by setting the minimum allowable value of thermal conductivity Rpi, it can be ensured that all evaluation samples meet specific quality standards, thereby improving the quality of the final product.

[0082] Placing the extracted X BGA packaged circuits on a thermal expansion test device, and heating each BGA packaged circuit based on preset conditions; the preset conditions are a heating temperature range and a heating rate;

[0083] During the heating process, the dimensional change data of each BGA package circuit at different set temperature points are recorded, and the thermal expansion coefficient of each BGA package circuit at different set temperature points is calculated accordingly;

[0084] Based on the thermal expansion coefficient of each BGA package circuit at different set temperature points, an expansion change trend diagram of each BGA package circuit is constructed;

[0085] Draw the numerical points corresponding to the thermal expansion coefficient of each BGA package circuit at different set temperature points in the expansion change trend diagram, and connect adjacent numerical points to obtain the coefficient line;

[0086] Calculate the slope of each coefficient line and the angle with the horizontal line. If the angle between a coefficient line and the horizontal line is an acute angle, mark the slope of the coefficient line as a descending slope. If the angle between a coefficient line and the horizontal line is an obtuse angle, mark the slope of the coefficient line as an ascending slope. Sum all the ascending slopes and descending slopes to obtain the total ascending value and the total descending value. Calculate the ratio of the total ascending value to the total descending value of each BGA package circuit, that is, calculate by the total ascending value / the total descending value, and use the calculated ratio as the expansion ratio Ms i of each BGA package circuit.

[0087] If the total value of the decrease is 0, the total value of the decrease is directly recorded as 1 to avoid the calculation process being invalid;

[0088] The average value of the thermal expansion coefficient of each BGA package circuit at different set temperature points is calculated, and the calculated average value is used as the expansion mean value Mhi of each BGA package circuit;

[0089] The maximum allowable expansion ratio and the maximum allowable expansion mean value corresponding to the BGA package circuit expansion ratio Ms i and the expansion mean value Mh i are respectively preset, and the maximum allowable expansion ratio and the maximum allowable expansion mean value are marked as Ls i and Lh i respectively;

[0090] According to the formula The expansion ratio Ms i and the expansion mean Mh i of each BGA package circuit are weightedly calculated, thereby obtaining the thermal expansion performance value Mq i of each BGA package circuit; wherein c1 and c2 are the influence weight factors of the expansion ratio Ms i and the expansion mean Mh i, respectively;

[0091] It should be noted that by comparing the actual measured value with the preset maximum allowable value, the reliability and potential risks of the material in actual application can be evaluated; the thermal expansion performance value obtained by weighted calculation can be used as a basis for quality control to ensure that the product meets specific performance standards.

[0092] Extract the thermal conductivity performance value Rn i and the thermal expansion performance value Mq i of each BGA package circuit, calculate the average value of the thermal conductivity performance value Rn i and the thermal expansion performance value Mq i of each BGA package circuit, and use the calculated average value as the thermal conductivity evaluation index and thermal expansion evaluation index of the BGA package circuit of the current production batch;

[0093] Based on the thermal conductivity evaluation index and thermal expansion evaluation index of the BGA packaged circuit of the current production batch, the index value ranges of each group corresponding to the thermal conductivity evaluation index and the thermal expansion evaluation index are preset respectively, and each group of index value ranges corresponding to the thermal conductivity evaluation index is set to correspond to a thermal conductivity score, and each group of index value ranges corresponding to the thermal expansion evaluation index is set to correspond to a thermal expansion score;

[0094] The higher the thermal conductivity evaluation index, the higher the thermal conductivity score obtained by the corresponding match, and the higher the thermal expansion evaluation index, the lower the thermal expansion score obtained by the corresponding match;

[0095] The thermal conductivity evaluation index and thermal expansion evaluation index of the BGA packaged circuit of the current production batch are matched with the corresponding preset index value ranges of each group, thereby obtaining the thermal conductivity score and thermal expansion score of the BGA packaged circuit of the current production batch, and the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch is obtained by accumulating the thermal conductivity score and the thermal expansion score;

[0096] It should be noted that a standardized scoring system was established by presetting the index value range and the corresponding scores, so that the thermal performance between different production batches can be compared and evaluated; the accumulation of thermal conductivity scores and thermal expansion scores results in a thermal performance evaluation index, which provides a quantitative indicator for quality control.

[0097] Preset three groups of index value ranges corresponding to the thermal performance evaluation index Gtr, set the three groups of index value ranges to correspond to a thermal performance level respectively, and the thermal performance levels include excellent level, good level and poor level; match the thermal performance evaluation index Gtr of the current production batch of BGA packaged circuits with the preset three groups of index value ranges, thereby obtaining the thermal performance level of the current production batch of BGA packaged circuits;

[0098] It should be noted that after obtaining the thermal performance level of the BGA packaged circuit of the current production batch, personnel can randomly select X BGA packaged circuits from the qualified workshop as evaluation samples for thermal performance testing as needed, and evaluate the thermal performance level again to improve the accuracy of the evaluation.

[0099] The report generation module is used to fill the inspection data of the current production batch of BGA packaged circuits into a preset template, so as to generate an inspection report of the current production batch of BGA packaged circuits; wherein the inspection data includes the number of qualified workshops, the number of repair workshops, the number of scrapped workshops and the thermal performance level of the BGA packaged circuits;

[0100] The above formulas are obtained by collecting a large amount of data and performing software simulation, and a formula close to the actual value is selected. The influencing weight factor and specific coefficient value in the formula are set by technical personnel in this field according to actual conditions, and can be adjusted and modified later.

[0101] Example 2, please refer to Figure 2As shown, based on the automated detection system for BGA package circuit quality provided in Example 1 of the present application, Example 2 of the present application proposes an automated detection method for BGA package circuit quality. Example 2 is only a preferred method of Example 1, and the implementation of Example 2 will not affect the independent implementation of Example 1;

[0102] An automated detection method for BGA package circuit quality, comprising:

[0103] S1: The BGA packaged circuit is placed on the detection position of the automated detection platform through the automated sorting equipment, and the image information of the BGA packaged circuit is collected and analyzed through the high-resolution camera to obtain the defect evaluation index Qer of the BGA packaged circuit;

[0104] S2: According to the defect evaluation index Qer of the BGA packaged circuit, the quality level of the BGA packaged circuit is determined and sent to the workshop of the corresponding quality level; the quality level includes qualified level, defective level and scrap level, and the corresponding workshops are qualified workshop, repair workshop and scrap workshop respectively;

[0105] S3: Randomly select X BGA packaged circuits from the qualified workshop as evaluation samples for thermal performance testing, and test and analyze the thermal performance parameters of each evaluation sample, thereby obtaining the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, and based on the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, obtain the thermal performance grade of the BGA packaged circuit of the current production batch; the thermal performance parameters include thermal conductivity and thermal expansion coefficient;

[0106] S4: Filling the inspection data of the BGA packaged circuit of the current production batch into a preset template, thereby generating an inspection report of the BGA packaged circuit of the current production batch; wherein the inspection data includes the number of qualified workshops, the number of repair workshops, the number of scrapped workshops and the thermal performance level of the BGA packaged circuit;

[0107] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An automated detection system for BGA package circuit quality, characterized in that: include: Image acquisition module: Place the BGA package circuit on the detection position of the automated detection platform, collect image information of the BGA package circuit and send it to the defect assessment module; Defect evaluation module: receives image information of BGA package circuit and analyzes it to obtain defect evaluation index Qer of BGA package circuit; Quality sorting module: According to the defect evaluation index Qer of the BGA packaged circuit, the quality level of the BGA packaged circuit is determined and sent to the workshop of the corresponding quality level; the quality level includes qualified level, defective level and scrap level, and the corresponding workshops are qualified workshop, repair workshop and scrap workshop respectively; Performance evaluation module: X BGA packaged circuits are randomly selected from the qualified workshop as evaluation samples for thermal performance testing, and the thermal performance parameters of each evaluation sample are tested and analyzed, thereby obtaining the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch. Based on the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, the thermal performance level of the BGA packaged circuit of the current production batch is obtained; the thermal performance parameters include thermal conductivity and thermal expansion coefficient; Report generation module: fills the inspection data of the BGA package circuit of the current production batch into the preset template, thereby generating the inspection report of the BGA package circuit of the current production batch; The inspection data include the number of qualified workshops, the number of repair workshops, the number of scrapped workshops and the thermal performance level of BGA packaged circuits.

2. The automatic detection system for BGA package circuit quality according to claim 1, characterized in that: Receive image information of BGA package circuit and analyze it, specifically: After receiving the image information of the BGA package circuit, the image information is converted into a grayscale image; the grayscale image is converted into a binary image so that the solder joint area is separated from the background; Based on the gray value of each solder joint area, the gray mean and standard deviation are calculated; A reference threshold range of gray values ​​is set, and the reference threshold range is the difference between the gray mean and two times the standard deviation to the sum of the dust mean and two times the standard deviation; based on the set reference threshold range, the solder joint areas with gray values ​​higher or lower than the set reference threshold range are marked as abnormal areas; the number of abnormal areas is counted and recorded as the number of abnormalities Ea; for each group of abnormal areas, the gray values ​​of each abnormal area are extracted, and corresponding calculations are performed based on the comparison results with the reference threshold range. If the gray values ​​of a group of abnormal areas are higher than the reference threshold range, the difference between the gray values ​​of the group of abnormal areas and the highest value in the reference threshold range is calculated; if the gray values ​​of a group of abnormal areas are lower than the reference threshold range, the difference between the gray values ​​of the group of abnormal areas and the lowest value in the reference threshold range is calculated, and the absolute value is taken; The difference calculated for each group of abnormal areas is extracted, and the average is taken to obtain the abnormal mean value Eb; the number of pixels in each group of abnormal areas is calculated, and the number is accumulated to obtain the abnormal face value Ec.

3. The automatic detection system for BGA package circuit quality according to claim 2, characterized in that: The defect evaluation index Qer of the BGA package circuit is obtained, specifically: According to the formula The abnormal number Ea, abnormal mean Eb and abnormal face value Ec of the BGA packaged circuit are weightedly calculated to obtain the defect evaluation index Qer of the BGA packaged circuit; wherein Va, Vb, Vc represent the maximum allowable abnormal number, maximum allowable abnormal mean and maximum allowable abnormal face value Ec corresponding to the abnormal number Ea, abnormal mean Eb and abnormal face value Ec, respectively, and t1, t2 and t3 are the influencing weight factors of the abnormal number Ea, abnormal mean Eb and abnormal face value Ec, respectively.

4. The automatic detection system for BGA package circuit quality according to claim 1, characterized in that: According to the defect evaluation index Qer of the BGA packaged circuit, the quality level of the BGA packaged circuit is determined and transported to the workshop with the corresponding quality level, specifically: Three groups of index value ranges of the preset defect assessment index Qer are set, and the three groups of index value ranges are set to correspond to the qualified grade, the defective grade and the scrap grade respectively; the defect assessment index Qer of the BGA packaged circuit is matched with the preset three groups of index value ranges, thereby obtaining the quality grade of the BGA packaged circuit; based on the quality grade of the BGA packaged circuit, the BGA packaged circuit is transported to a workshop of the corresponding quality grade.

5. The automatic detection system for BGA package circuit quality according to claim 4, characterized in that: If the number of BGA packaged circuits delivered to the defective workshop exceeds the processing quantity threshold set for the workshop, the adjustment signaling will be triggered, and the BGA packaged circuits that exceed the processing quantity threshold will be marked and delivered to the scrap workshop.

6. The automatic detection system for BGA package circuit quality according to claim 1, characterized in that: The thermal performance parameters of each evaluation sample were tested and analyzed, specifically: Apply heat to each BGA package circuit based on preset conditions; record the thermal conductivity value obtained by testing each BGA package circuit Y times; where Y>4; calculate the average value of each group of thermal conductivity values ​​obtained by testing each BGA package circuit, and use the calculated average values ​​of each group as the thermal conductivity average value Rdi of each BGA package circuit; Where i represents the number of the extracted BGA package circuit, i=1,2...X; At the same time, the highest value and the lowest value are extracted from each group of thermal conductivity values ​​obtained by testing each BGA package circuit, and are used as the thermal conductivity peak value Rci and the thermal conductivity valley value Rhi of each BGA package circuit respectively; The minimum allowable value of the thermal conductivity value corresponding to the BGA package circuit is preset; the preset minimum allowable value is marked as Rpi; Using the formula The thermal conductivity mean value Rdi, thermal conductivity peak value Rci and thermal conductivity valley value Rhi of each BGA package circuit are weightedly calculated to obtain the thermal conductivity performance value Rni of each BGA package circuit; wherein u1, u2 and u3 are the influencing weight factors of the thermal conductivity mean value Rdi, the thermal conductivity peak value Rci and the thermal conductivity valley value Rhi respectively.

7. The automatic detection system for BGA package circuit quality according to claim 1, characterized in that: The thermal performance parameters of each evaluation sample are tested and analyzed, including: Heat each BGA package circuit based on preset conditions; during the heating process, record the size change data of each BGA package circuit at different set temperature points, and calculate the thermal expansion coefficient of each BGA package circuit at different set temperature points; construct an expansion change trend diagram of each BGA package circuit based on the thermal expansion coefficient of each BGA package circuit at different set temperature points; Draw the numerical points corresponding to the thermal expansion coefficient of each BGA package circuit at different set temperature points in the expansion change trend diagram, and connect adjacent numerical points to obtain the coefficient line; Calculate the slope of each coefficient line and the angle with the horizontal line. If the angle between a coefficient line and the horizontal line is an acute angle, mark the slope of the coefficient line as a descending slope. If the angle between a coefficient line and the horizontal line is an obtuse angle, mark the slope of the coefficient line as an ascending slope. Sum all the ascending slopes and descending slopes to obtain the total ascending value and the total descending value. Calculate the ratio of the total ascending value to the total descending value of each BGA package circuit, that is, calculate by total ascending value / total descending value, and use the calculated ratio as the expansion ratio Msi of each BGA package circuit. The average value of the thermal expansion coefficient of each BGA package circuit at different set temperature points is calculated, and the calculated average value is used as the expansion mean value Mhi of each BGA package circuit; The maximum allowable expansion ratio and the maximum allowable expansion mean value corresponding to the BGA package circuit expansion ratio Msi and the expansion mean value Mhi are respectively preset, and the maximum allowable expansion ratio and the maximum allowable expansion mean value are marked as Lsi and Lhi respectively; According to the formula The expansion ratio Msi and the expansion mean Mhi of each BGA package circuit are weightedly calculated, thereby obtaining the thermal expansion performance value Mqi of each BGA package circuit; wherein c1 and c2 are the influencing weight factors of the expansion ratio Msi and the expansion mean Mhi respectively.

8. The automatic detection system for BGA package circuit quality according to claim 1, characterized in that: The thermal performance evaluation index Gtr of the BGA package circuit of the current production batch is obtained, specifically: Extract the thermal conductivity performance value Rni and the thermal expansion performance value Mqi of each BGA package circuit, calculate the average value of the thermal conductivity performance value Rni and the thermal expansion performance value Mqi of each BGA package circuit, and use the calculated average value as the thermal conductivity evaluation index and thermal expansion evaluation index of the BGA package circuit of the current production batch; Based on the thermal conductivity evaluation index and thermal expansion evaluation index of the BGA packaged circuit of the current production batch, the index value ranges of each group corresponding to the thermal conductivity evaluation index and the thermal expansion evaluation index are preset respectively, and each group of index value ranges corresponding to the thermal conductivity evaluation index is set to correspond to a thermal conductivity score, and each group of index value ranges corresponding to the thermal expansion evaluation index is set to correspond to a thermal expansion score; The thermal conductivity evaluation index and thermal expansion evaluation index of the BGA packaged circuit of the current production batch are matched with the corresponding preset index value ranges, thereby obtaining the thermal conductivity score and thermal expansion score of the BGA packaged circuit of the current production batch, and the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch is obtained by accumulating the thermal conductivity score and thermal expansion score.

9. The automatic detection system for BGA package circuit quality according to claim 1, characterized in that: Get the thermal performance level of the BGA package circuit in the current production batch, specifically: The three groups of index value ranges corresponding to the preset thermal performance evaluation index Gtr are set to correspond to a thermal performance level respectively, and the thermal performance levels include excellent level, good level and poor level; the thermal performance evaluation index Gtr of the current production batch of BGA packaged circuits is matched with the preset three groups of index value ranges, thereby obtaining the thermal performance level of the current production batch of BGA packaged circuits.

10. An automated detection method for BGA package circuit quality, applied to an automated detection system for BGA package circuit quality proposed in claims 1-9, characterized in that: include: S1: The BGA packaged circuit is placed on the detection position of the automated detection platform through the automated sorting equipment, and the image information of the BGA packaged circuit is collected and analyzed through the high-resolution camera to obtain the defect evaluation index Qer of the BGA packaged circuit; S2: According to the defect evaluation index Qer of the BGA packaged circuit, the quality level of the BGA packaged circuit is determined and sent to the workshop of the corresponding quality level; the quality level includes qualified level, defective level and scrap level, and the corresponding workshops are qualified workshop, repair workshop and scrap workshop respectively; S3: Randomly select X BGA packaged circuits from the qualified workshop as evaluation samples for thermal performance testing, and test and analyze the thermal performance parameters of each evaluation sample, thereby obtaining the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, and based on the thermal performance evaluation index Gtr of the BGA packaged circuit of the current production batch, obtain the thermal performance grade of the BGA packaged circuit of the current production batch; the thermal performance parameters include thermal conductivity and thermal expansion coefficient; S4: Filling the inspection data of the BGA packaged circuit of the current production batch into a preset template, thereby generating an inspection report of the BGA packaged circuit of the current production batch; The inspection data include the number of qualified workshops, the number of repair workshops, the number of scrapped workshops and the thermal performance level of BGA packaged circuits.

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