The mask is a known contributor to intra-field and local patterning fingerprints at the wafer level. Traditionally, a 3σ distribution of critical dimensions (CDs) on mask was sufficient to characterize the contribution to the CD distribution at wafer level. However, as edge placement error (EPE) and EUV wafer patterning stochastics become critical with decreasing feature sizes, wafer CD distributions are being characterized for statistics beyond 3σ. Additionally, Local Placement Error (LPE) is a critical metric that is expected to contribute to EPE. Consequently, it is imperative to understand, characterize and control the EUV mask contributors to the EPE budget. This work is an attempt to extensively characterize the CD and LPE distribution on an EUV mask and identify its impact at wafer level.
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