New Design Based Metrology for Fast Detection of Crucial Lithographic Defects

Abstract

In this paper, we proposed a new design based metrology system to save runtime for the detection of crucial lithographic defects. To the best of our knowledge, we developed for the first time the weak point management system that is a database control environment with the repeated design related systematic defects after model-based verification. Then, the defects are again verified with design based metrology (DBM). Using the result of model-based verification and the weak point management system, we efficiently verify the most crucial hotspots with DBM, resulting in significant saving in processing time. The communication between DBM and the results of model based verification is improved by the proposed DBM, as much as 10-fold process time reductions, compared to the conventional counterpart. There was negligible accuracy degradation for the application on sub 50 nm node dynamic random access memory (DRAM). We believe that the proposed method can be used for the next DRAM generation that requires significant runtime.