Sub-resolution process windows and yield estimation technique based on detailed full-chip CD simulation

摘要

Conventional methods of CD-limited yield and process capability analysis either completely ignore the intra-die CD variability caused by the optical and process proximity effects or assume it is nor mally distributed. We show that these assumptions do not hold for the aggressive subresolution designs. The form and modality of intra-die poly-gate CD variability strongly depend on the defocus and exposure values. We study the influence of process parameters on strong phase shifted and binary mask designs. A definition of a CD-based process window is proposed to capture the "proximity signature" of the design and its dependence on process parameters.