Accelerate OPC convergence with new iteration control methodology

摘要

A dilemmatic trade-off that all OPC engineers are facing everyday is the convergence of the OPC result andthe control of the OPC iteration times. Theoretically, infinite times of OPC iterations are needed to achieve aconvergent and stable correction result. But actually there should always be a cut-off for the iteration time, for turn-around-time is always an important criteria for IC fabs. But considering the design layout becomes more complicatedand pattern density becomes higher with the shrinkage of the critical dimension, fragmentation control during theOPC procedure is also becoming more and more sophisticated. Thus, to achieve a convergent correction result for allOPC fragments within limited correction iteration times now becomes a big challenge to OPC engineers. This workpresents our study in a new OPC iteration control methodology. It can help to find an algorithm that alwaysconverges, and reduce the excessive use of parameter setting, commands and other involvement by the user. Withthis, we can reduce the run time required to obtain a convergent OPC solution.