A POLISHING LIQUID FOR CHEMICAL-MECHANICAL ABRADING

摘要

The present invention discloses a polishing liquid for chemical-mechanical abrading comprising water, abrasive particles and oxidant, wherein the oxidant comprises nitrate and metal salt at the same time. The cation of the nitrate is metallic ion or non metallic ion. The cation of the metal salt is different from that of the nitrate while the cation of the nitrate is metallic ion. The present polishing liquid can be effectively used for chemical-mechanical polishing of metal tungsten in semiconductor material by utilizing the synergistic effect between the nitrate and the metal salt. Moreover, it has lower concentration of metal ion which tends to contaminate the mesa and parts of CMP apparatus. It has little contamination to the mesa of CMP apparatus. At the same time, it can also ensure the polishing liquid having stable property for a long time without storing the components of the polishing liquid separately. So the operating steps of CMP are omitted.