Copper pullout

ECP in DI water shows promise in planarization performance. However, owing to poor electrical conductivity of the ion-exchange film to the wafer, it has to resort to a high current during polishing, which may lead to defects such as copper pullouts. Until this issue is addressed, the ECP-DI approach will be difficult to implement for copper polishing process at industrial level. 

Cobalt salts used in the wire coat compounds may accelerate the vulcanization rate of high sulfur compounds, and increase the state of cure or crosslink density. The increase in crosslink density increases the pullout force of the wire in the rubber. More important, cobalt salts form Co + ions at the interface of the brass surface during vulcanization, and this will affect copper sulfide formation. 

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