Application of OPE Master for Critical Layer OPE Matching

Tool-to-tool matching of optical proximity effect (OPE) properties is required and the procedure is called OPE matching. Nikon has developed a software called OPE Master for the purpose, which can decrease OPE errors with emphasis placed on critical dimension (CD) errors by optimizing exposure tool's parameters, such as lens numerical aperture (LNA), pupilgram intensity distribution, pupilgram distortion. Thanks to its high affinity to the Nikon NSR series scanners, the software ensures higher accuracies and short turn-around-time (TAT) as it can directly communicate with exposure tools. One secondary benefit of such bilateral communication is that it can realize high data security as we have no need to send data used during OPE matching to the outside of the fab. In this paper, we are going to introduce OPE Master and report one successful use case. which is a critical layer in 55nm node in which OPE errors has been improved by about 33% which is well within the goal of the process requirements.