A new method for model based frugal OPC

Improvements on resolution enhancement technologies (RETs) enable minimum feature size of IC to shrink consistently with Moore's Law. However growing mask data volume also tremendously increases manufacture cost. The cost increase is partially due to the complicated optical proximity corrections applied on mask design. Frugal OPC methods have been introduced to reduce the complexity. In this paper, a new method for frugal OPC is presented. Based on recognition of critical spots under yield related constraints, the new correction flow keeps fidelity on critical sites while still retaining the frugality of modified designs.