A BASIC STUDY ON METAL CMP MECHANISM AND A TRIAL FOR PRODUCING CMP SLURRY BY SOL-GEL METHOD

点击翻译按钮获取中文摘要

Today, the drastic change of our life to the information society has been brought by the rapid popularization of computers, which are associated with highly integrated IC and LSI. The production of IC and LSI depends upon the development of micro-precision processing technologies. Chemical Mechanical Polishing(CMP) is the typical technology necessary for producing multi-layer circuits of IC and LSI by the damascene method on a silicon wafer, where the surface of each circuit layer must be made to be perfectly smooth. The required flatness for the surface finished by CMP in production process would be now less than 100 Å.In this study, first of all, production of colloidal silica slurry for CMP by sol-gel method was conducted in trial in our laboratory. Therefore, constitutions of the slurry used for the experiment are known clearly. Then, polishing experiments for glass materials were carried out with the trial slurry and its polishing properties such as stock removal, surface roughness, polishing torque, etc. were investigated under various polishing conditions (i.e., pH, grain size, slurry density of grains, pad material, etc.), comparing polishing properties of marketed slurries which include some unknown additives. As a result, we formulate a CMP mechanism model and it was proved that some polishing properties obtained in the experiments could be explained by the CMP mechanism modelOn the basis of the results obtained above, we conducted Metal CMP experiments and discussed Metal CMP mechanism. Finally, we get to a conclusion that there exists a similarity between Si CMP and Metal CMP, though it is complicated phenomena.