Triple patterning aware detailed placement toward zero cross-row middle-of-line conflict

Triple patterning lithography (TPL) is one of the most promising lithography technology in sub-14nm technology nodes, especially for complicated low metal layer manufacturing. To overcome the intra-cell routability problem and improve the cell regularity, recently middle-of-line (MOL) layers are employed in standard cell design. However, MOL layers may introduce a large amount of cross-row TPL conflicts for row based design. Motivated by this challenge, in this paper we propose the first TPL aware detailed placement toward zero cross-row MOL conflict. In standard cell pre-coloring, boolean based look-up table is proposed to reduce solution space. In detailed placement stage, two powerful techniques, i.e., local reordered single row refinement (LRSR) and min-cost flow based conflict removal, are proposed to provide zero TPL conflict solution. The experimental results demonstrate the effectiveness of our proposed methodologies.