Concurrent Guiding Template Assignment and Redundant via Insertion for DSA-MP Hybrid Lithography

Abstract

Directed Self-Assembly (DSA) is a very promising emerging lithography for 7nm and beyond, where a coarse guiding template produced by conventional optical lithography can "magically" generate fine-pitch vias/contacts through self-assembly process. A key challenge for DSA-friendly layout is the guiding template assignment to cover all vias under consideration. Meanwhile, redundant via insertion has been widely adopted to improve yield and reliability of the circuit. In this paper, we propose a comprehensive framework for concurrent DSA guiding template assignment and redundant via insertion with consideration of multiple patterning (MP) in guiding template generation. We first formulate the problem as an integer linear programming (ILP), and then propose a novel approximation algorithm to achieve good performance and runtime trade-off. The experimental results demonstrate the effectiveness of the proposed algorithms. To our best knowledge, this is the first work in concurrent guiding template assignment and redundant via insertion for DSA-MP hybrid lithography.