Static and dynamic interaction between polyvinyl acetal brushes and flat surfaces-Measuring near-surface brush volume ratio and nodule volume change for moving brushes

The cleaning mechanism for brush scrubbing, known as the contact-type cleaning method, utilizes the direct contact of impurities onto brushes or brush-induced fluid flow depending on the contact condition. Applying brush cleaning to nanosized defects in advanced semiconductor manufacturing requires understanding of the interaction between the brush and scrubbing surface under actual operating conditions. We observed the near-surface brush volume ratio and brush nodule deformation using high-speed photography to obtain insights into efficient nanosized cleaning. Evanescent fields on a prism and a convex lens facilitate the definition of the observation depths of several hundred nanometers. Starting rotation experiments revealed a drastic reduction in the brush volume ratio, indicating that the static contact is far from the dynamic contact. The volume change during roller brush nodule deformation depends on the surface material. Furthermore, large friction materials exhibit large deformation and rapid recovery. These nodule deformations may generate a different fluid flow near the surface owing to the brush's fluid absorption and desorption.

Automated summary

The contact-type cleaning method, which involves direct contact of impurities with brushes or brush-induced fluid flow, is used for brush scrubbing. When applying brush cleaning to nanosized defects in advanced semiconductor manufacturing, it is important to understand the interaction between the brush and scrubbing surface under actual operating conditions. High-speed photography was used to observe the brush volume ratio and brush nodule deformation near the surface, providing insights into efficient nanosized cleaning.