Nanoparticle-Polymer Surface Adsorption Relevant to CMP Applications

Abstract

Chemical Mechanical Polishing (CMP) has emerged as a critical technology for the planarization of precision optical components, data storage media, and integrated circuit semiconductor devices. This process is a delicate balance between chemical surface modification and mechanical removal utilizing a nanoparticle dispersion (slurry) to remove defects/irregularities with the goal to attain angstrom level uniformity. As technology continues to advance, next generation nanoparticle dispersions and CMP slurries will increase in complexity to meet stringent performance demands, making it necessary to develop polymeric media that reduce overall surface defectivity and increase planarization efficiency. To uncover dynamics amongst the slurry additives, abrasives, polymeric interfaces, and the CMP substrate the molecular level interactions at the nanoparticle-polymer interface need to be explored. This work set out to explore these interaction mechanisms by using a modified electrochemical quartz crystal nanobalance (EQCN) technique. This modified technique utilizes thin film deposition to place a polymer on the electrode and then by applying the Sauerbrey equation it is possible to gain insight about the surface adsorption at the nanoparticle-polymer interface. The synergistic interaction of the slurry chemistry and the polymeric substrate is further explored to determine the role of surface reactions that alter the polymeric medium’s surface energy and subsequently alter the nanoparticle binding mechanisms.