Key Technologies Research On BGA Solder Joint’s Defect Detection Based On Precision Micro-focus X-ray

BGA (Ball Grid Array) package is a highly integrated modern circuit device packagingtechnology. The structural complexity of the PCB (Printed Circuit Board) assembly productswith BGA components usually leads to the difficulty in BGA solder joint defect detection.To solve this difficulty in BAG solder joint inspection, this papers focus on study theBAG defect detection algorithms in complex image background, which mainly consist offollowing four aspects:(1) The Research of BGA solder joint contour extraction method is conducted. Medianfilter and Gaussian filter are used to image filtering. And the solder joints are divided into twocategories: the first category is not blocked joints; second category is obscured joints. Forunblocked joints, we propose a method to contour extraction based on Otsu thresholdsegmentation, regional location, edge detection and contour extraction contour tracing. Forblocked solder joints, this paper presents an interactive contour extraction method to completethe contour extraction.(2) The research on BGA solder void contour extraction method is conducted. Then, wepropose a method to complete the void extraction, based on top hat morphological operation,fuzzy enhancement, histogram stretch, Otsu threshold, Blob analysis connectivity analysis.(3) Research on BGA solder joint defects classification is conducted. The soldercharacteristics are computed and a method is proposed to realize classification of BGA solderjoint defects.(4)Experimental research is conducted in this section.Comparing with the FLW-3000, SMT160.15, the result shows that the proposedalgorithm can detect BGA solder joint inspection under the complex background, and is betterthan FLW-3000, SMT160.15algorithm.The paper researches on BGA solder joint defect detection based on the research ofprecision micro-focus X-ray, able to complete the detection of solder joint defect detection.The experiment shows that the paper algorithm can propose appropriate detection algorithms to complete can accurate detection of solder defects.