Shake it off - Real-time dynamics of particle release by vibration

The size of features on microcontroller chips continues to shrink. This causes an increasing challenge for contamination control, because defects can be caused by smaller and smaller contaminating particles. Most of the contaminations are found on various surfaces. Therefore there is an increased interest in particle removal methods. What mechanisms can cause particles to be removed and when will they stick to the surface? To answer this we need a quantitative understanding of possible removal mechanisms. Therefore it is crucial to first know the adhesive particle bounding force. We have developed a technique to measure this using vibrating piezo elements. With this we will be able to quantitatively determine the effectiveness of a novel cleaning method such as plasma-enhanced particle lofting. Our real-time dynamics measurements allow us to view individual particle behaviour on the vibrating surface. This has revealed more complicated behaviour than would be naively expected. In this contribution we will show some examples of this. The shown results are immediately useful for industrial application, because vibrating surfaces are inherently present in any production environment.