Development of high speed Copper CMP slurry for TSV application based on friction analysis

In order to obtain high speed Cu CMP process for TSV application, we have developed new Copper CMP slurry through friction analysis of Cu reaction layer with an AFM technique. Lateral Modulation Friction Force Microscope (LM-FFM) is the one that is able to measure the friction properly giving a vibration to the layer. We evaluated the torsional displacement between the probe of the LM-FFM and Cu reaction layer under the 5 nm vibration to cancel the shape effect of the Cu reaction layer. The developed Cu CMP slurry makes the frictionally easy-removable Cu reaction layer.