In this paper, a study of CMP behaviors on three different kind of aromatic polymers is presented. The removal mechanism on the elastic polymer-based materials was found to be different from that of metal or oxide. Polymer is actually scrapped away instead of polishing and Preston's equation is not followed. Therefore, down force dominates the removal of polymer from the sub-layer. On the other hand, oxide removal rate is proportional to PV product. In order to remove polymer and to minimize the loss on sub-layer, such as oxide as a typical example, a recipe with low PV product was developed to achieve high selectivity between polymer and sub-layer. The results show that the low PV recipe can remove polymer efficiently as well as the sub-layer loss is minimized. A new process (GFP) utilizing this polymer CMP approach to get a better process margin is also briefly described in this study.
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