A Robustness Study on Self-Alignment of Thin-Si Dies Using Surface Tension

Abstract

We found that self-alignment accuracy was better than ±2 μm in the case with an initial offset of up to 1 mm. This method, driven by the surface tension force of the liquid, offers new technical solutions for both high accuracy chip bonding and low cost placement manner. Some important points, such as wetting behaviour, die release offset, and the influence of defects on a die, were studied in order to suggest approaches to robustness in this new technique.

Plasma dicing enables high accuracy self-alignment of thin silicon dies for 3D-device-integration

“…In the case of larger dies (> 5 mm side length) we found many dies showing a self-alignment accuracy of less than 1 µm. Larger displacements seem to be linked with increasing number of particulates and dust on the surfaces after repeated use of bottom substrates [8]. Also for small dies (1x1 mm 2 , 2x2 mm 2 ) accurate self-alignment was observed.…”