Abstract
Polyvinyl acetal (PVA) brushes have been widely used in the post CMP cleaning. To better understanding the cleaning mechanisms of PVA brushes, we measured the friction force between PVA roller brushes and semiconductor wafers with various films in chemicals. As a result, the friction force was decreased with increase of pH of chemicals. On the other hand, combinations of W or Cu and NH_4OH only showed large friction force. Furthermore, the friction force was decreased with the increase of the rotation speed in citric acid or ultra pure water. In contrast, the friction force was increased with the increase of the rotation speed in NH_4OH.
