In this paper, an optical inspection method of the ball grid array package(BGA) is proposed using a binocular machine vision system.
The height of each solder ball is calculated based on spatial geometrical size and location obtained from the two CCD cameras capturing range images of a LED illuminated BGA chip at certain orientation.
The structure of this system is simple and the accuracy is 0.02 mm, The experimental results have proved the validity of this system for BGA failure detection.
The developed machine vision system can provide some of the critical factors for BGA quality evaluation, such as the height of solder ball, diameter, pitch and coplanarity.
Compared with other systems, the structure of this system is simple and accurate, which meets the demand of off‐line and on‐line inspection. The limitation of this system is that the margin of field of view (FOV) is fuzzy. Further study could be focused on this problem.
Qixin, C., Zhuang, F., Nianjiong, X. and Lewis, F.L. (2005), "A binocular machine vision system for ball grid array package inspection", Assembly Automation, Vol. 25 No. 3, pp. 217-222. https://doi.org/10.1108/01445150510610935Download as .RIS
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