Optimizing process window robustness with reconfigurable OPC

摘要

In this work, a reconfigurable optical proximity correction (OPC) approach is taken to enhance process window robustness for sub-100nm designs. First, a physics-based method for lithography process window verification is used to provide better accuracy at off-focus and off-exposure conditions and to reduce calibration efforts, as compared to traditional empirical approaches. After multiple defocus and exposure conditions are simulated, reconfigurable OPC is used to fix only defective areas and to replace them with optimized corrections, thereby avoiding the possibility of generating new errors when fixing problematic patterns. This combined approach provides an optimal lithography solution that is robust across the process window, and a mask design inspection and optimization method that improves yield and shortens cycle time to first wafers.