CTM-SRAF: Continuous Transmission Mask-Based Constraint-Aware Subresolution Assist Feature Generation

Ziyang Yu, Peiyu Liao, Yuzhe Ma, Bei Yu, Martin D. F. Wong

2023IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems19 citationsDOI

Abstract

In the lithography process, subresolution assist features (SRAFs), as an essential resolution enhancement technique (RET), is applied to improve the pattern fidelity and enlarge the process window. In this article, we propose a robust constraint-aware SRAF generation method based on continuous transmission mask (CTM). The intensity distribution on the CTM is extracted to guide the SRAF generation. The SRAF insertion also honors the design rules, which is formulated as integer programming with quadratic constraints and solved by a fast yet efficient algorithm. A fast probe-based SRAF evolution method is proposed to determine the shapes of SRAFs. The effectiveness and efficiency are demonstrated based on the experimental results.

Topics & Concepts

Computer scienceAlgorithmProcess (computing)Constraint (computer-aided design)Feature (linguistics)Process windowMathematical optimizationMathematicsOperating systemLinguisticsPhilosophyGeometryAdvancements in Photolithography TechniquesImage Processing Techniques and ApplicationsAdvanced Image Processing Techniques