An automated assessment method for integrated circuit chip detachment from printed circuit board by multistep binarization and template matching of X-ray transmission images

Abstract

Given the increase in digital product waste, demand for recycling of printed circuit boards (PCBs) is increasing. Precious and minor metals are often well concentrated in integrated circuit (IC) chips, especially in PCBs; hence, IC chips are primary targets for recycling. The technology for the non-destructive detachment of IC chips from PCBs is increasing in sophistication; however, the effectiveness of IC chip detachment is currently assessed manually and visually. In the present study, an automated IC chip detachment assessment method was developed, which combines multistep binarization and template matching of X-ray transmission images of crushed PCBs. To validate the method, five types of mechanically crushed PCBs from mobile phones were examined, and the developed method successfully assessed the IC chip detachment rate, with an average error rate of only 2.2% compared to visual assessment.

Analysis of thermal-offset drift of a high-resolution current probe using a planar Hall resistance sensor

“…Additionally, it can be challenging to detect defects through voltage waveforms in situations such as minute disconnections in the signal line or when floating occurs within the circuit. Therefore, other metrologies like X-ray transmission (Ueda et al, 2021;Roh et al, 2003), infrared imaging (Zhang et al, 2014;Huang and Wu, 2010), or eddy current measurement (Koggalage et al, 2005;Chomsuwan et al, 2007) have been additionally applied for the analysis. However, these kinds of methods also have limits for overall analyses because they are partially helpful for finding some physical defects such as disconnections or shorts.…”