Novel One-Dimensional Scattering Bar Rule via Computer Aided Design

Although one-dimensional scattering bars (SB) are designed to consolidate photolithography patterns to extend process tolerance, but the inability of covering diverse layout environments by employing simple SB rules collected from empirical measurements makes it impossible to utilize SB as a reliable resolution enhancement technology (RET). Therefore, this study presents a novel one-dimensional SB scheme called computational scattering bar rule (CSBR) that assures line-space layouts get suitable SB. An empirical data can be measured and a physical model can then be built to fit the data. Next, basing on such model, wafer images are simulated over numerous critical dimensions (CD) of main feature (MF) with different SB widths and SB spaces to locate optimized SB rules. Two approaches of optimization strategies are proposed to meet different requirements, and are verified by commercial software. This novel scheme significantly contributes to utility of SB.