Properties and chemical-mechanical polishing characteristics of low dielectric constant polymer films: PAE-2 and Flare 2.0

In this article, the film properties and chemical-mechanical polishing (CMP) characteristics of two different low dielectric constant poly (arylene ethers): PAE-2 and Flare 2.0 were studied. The molecular structure, thermal-stress properties, and dielectric constant of the polymer films were characterized. The removal rates and surface properties of the polished films were investigated by the following parameters: structural rigidity, types of abrasives, and various charge status of surfactants (Triton X-100 and DSSS). The experimental results show that the mechanical properties of polymer films, the abrasive hardness and surfactant affected significantly the CMP characteristics. The mechanical property of the PAE-2 film was inferior to the Flare 2.0 film and thus a higher polishing rate was found for the PAE-2 film than the Flare 2.0 film. The order of the removal rates for both polished films was 8105 > 8104 > SS-25, which was the same trend as the hardness of the abrasive. The addition of surfactants into the slurries significantly modified the surface contact area and the electrostatic force between the abrasive and the polymer film. Therefore, the polishing rate was affected by surfactants.