Optimal OPC model selection with SEM image contours

We propose a novel method to select a reliable OPC model by utilizing SEM image contours. In this proposal, the SEM image contours are extracted by Calibre SEMSuite™ and compared with simulation contours which are generated under different OPC models. Because the image contours are based on wafer SEM images, the selected model can have a higher accuracy to mimic the printed features on wafers. In addition, the model is selected deterministically since the comparison are taken under multi-dimensions with different weights and a final ranking score is evaluated for OPC model candidates. Our experiment demonstrates that the selection of a high-accurate OPC model is feasible with the present method.