Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 12, 2016 - November 13, 2016
PVA (Polyvinyl acetal) brushes have been widely used for a wet cleaning in semiconductor device fabrication. To better understanding the lubrication condition between a PVA brush and cleaning surfaces, we observed gas-liquid-solid interface using a total reflection microscope with polarization plates. First we investigated the real contact area of a POM (Polyoxymethylene) ball by applying a normal load in air and water. Then we observed the contact condition of a PVA brush. As a result, the observed real contact areas of the POM ball were agreed with the estimation from the Hertzian contact theory. In addition, the real contact area between a PVA brush and a glass plate in water was also able to observe. The real contact areas were increased with increase the normal force acting on the PVA brush. We concluded that the part of a PVA brush is contact with a cleaning surface.
