Manufacturability Enhancement With Dummy via Insertion for DSA-MP Lithography Using Multiple BCP Materials

The directed self-assembly and multiple patterning (DSA-MP) lithography has shown its great potential in fabricating via/contact layers in sub-10-nm technology nodes. Existing studies have shown that using two different block copolymer (BCP) materials can reduce conflict numbers among guiding templates compared with those only using a single BCP material. However, given an arbitrary via/contact layout, there may still be many conflicts in an optimized template design and mask assignment solution. In this article, we explore the possibility of via manufacturability improvement with dummy via insertion for DSA-MP. We also propose a post-decomposition optimization flow composed of four heuristics to further resolve conflicts. The experimental results show that our flow can efficiently and effectively reduce conflicts by inserting dummy vias.