Simulation-based source and mask optimization for advanced nodes

Lithography is a key and fundamental technology to drive the development of the integrated circuit. For advanced nodes, source mask optimization (SMO) has become a more and more promising technique to push the limits of the lithography. Thus, it is important to achieve the optimal settings in SMO to achieve the best source for lithography. In this paper, based on two target patterns, min pupil illumination efficiency of the source is optimized. Besides, better balance for dose latitude through focus is obtained. The effect of the target patterns weight on the result is demonstrated. Finally, we get a tuned source with the optimal parameters to cover the target patterns.