A Layout Decomposition Algorithm for Self-Aligned Multiple Patterning

摘要

Self-aligned multiple patterning (SAMP) is a promising technology to scale IC devices to 7-nm half pitch and several 3-mask negative-tone SAMP processes for 2-D BEOL patterning applications have been proposed recently. In this paper, the existing coloring rules in self-aligned quadruple and sextuple patterning (SAQP and SASP) processes are re-examined first. We further discuss the geometric relation between various features and remove the unnecessary constraints, and develop improved layout decomposition algorithms for both processes. The cut-mask related overlay issue is addressed by proposing an edge-expansion solution when generating the cut patterns. Finally, we show that numerous standard Ml cells in the Open Cell Library, when slightly modified, can be successfully decomposed. This verifies the functionality of the new decomposition algorithms for continuous logic scaling to deep nano-scale using SAMP techniques.