Non-Prestonian behavior of rectangular shaped ceria slurry in shallow trench isolation chemical mechanical planarization.

ABSTRACT

Rectangular ceria particles were synthesized using the flash creation method. The influence of the morphology of ceria particles and the surfactant concentration on the removal rate was systematically investigated. These ceria slurries with polymeric surfactant molecules as the passivation agents of Si3N4 film, shows an exceptional non-Prestonian behaviors. The non-Prestonian behavior can be attributed to the increase in the contact area of the ceria particles with the SiO2 film, which is dominated by the morphology of the ceria particles. Force measurements using an atomic force microscope (AFM) at different concentrations of polymeric surfactant molecules was used to identify the interactions between the polymeric molecules and the oxide film and analyze the non-Prestonian behavior of ceria slurry having rectangular abrasives.