The influence of heating temperature on alignment precision in thermosonic flip-chip bonding

According to the fact that heating will affect the image collection, target identification and track, so it will affect the alignment precision of the chips and substrates in the process of chips package. Sequence images were collected through the thermosonic flip-chip bonder under the different heating temperature, their parameters distribute regulation of translation, scale ,rotation under the influence of the temperature were respectively studied by phase correlation algorithm and 6-parameter affine model hierarchical search algorithm. The distributions of these parameters are highly random and nonlinear. To improve the algorithm speed, a hierarchical search algorithm based on the pyramid was adopted. By statistical analysis of the experimental results, it indicated that the higher the temperature, the higher the dispersion degree of translation, scale, rotation. So the temperature effects can not be ignored in thermosonic flip-chip bonding.