Comparison of slurry film distribution between a novel slurry injection system and conventional slurry application method

In this study, slurry film distribution on an embossed Politex pad was compared between a novel slurry injection system (SIS) and conventional slurry application method. The slurry injector was placed on top of the pad surface and it injected slurry in a thin layer at the device trailing edge using multiple injection points. Slurry was also applied to the pad center area using the conventional slurry application method. A fluorescent dye (4-methyl- umbelliferone) was added to the slurry. The slurry fluoresced under UV light and the fluorescent light was captured by a high resolution charged coupled device camera. Results showed that SIS provided a much more uniform slurry distribution to the pad-wafer interface than the conventional slurry application method.