ABSTRACT
Adding an appropriate chelating agent to SC-1 can remove, as well as prevent deposition of metallic impurities during the particle removal step and eliminate the need for a follow-up metallic impurity removal step [3, 4]. Not only does this reduce the number of chemical cleaning steps required, saving money and time, it also avoids the adverse effect of particle re-deposition during typical metallic im purity removal steps, such as SC-2 or an HF dip. Furthermore, an appropriately
chelate-enhanced SC-1 solution can potentially remove metallic contamination even more efficiently than SC-2 solution, and its ability to bind free metal ions in solution will potentially prevent process excursions from affecting process yield. In addition to enhancing the metallic cleaning ability of SC-1 solutions, we have also investigated the use of surfactants in our modified SC-1 solution.
