Double Patterning-Aware Detailed Routing with Mask Usage Balancing

Seong-I Lei1,  Chris Chu2,  Wai-Kei Mak1
1National Tsing Hua University, 2Iowa State University


Double patterning lithography (DPL) for 32nm and 22nm technology nodes requires decomposing a layout into two masks for lithography. It is important to consider DPL during the detailed routing stage so that the layout can be decomposed easily with the minimum number of stitches. In this paper, we propose a double patterning-aware detailed routing algorithm to balance the mask usage. Different from previous works, we first fix the color of each track in the routing grid and perform detailed routing using these pre-colored tracks. Experimental results demonstrate that our algorithm yields a significant improvement on the number of stitches and decomposability.