Full reticle curvilinear inline linearity correction including variable bias with zero turnaround time

This paper publishes for the first time a full Online reticle curvilinear Mask Process Correction that includes linearity correction due to variable bias for production use in a mask shop. Micron is readying ourselves for EUV use of free-form curvilinear ILT by anticipating the need for full reticle processing of Mask Process Correction (MPC) including dose-based near-term and mid-range effects and variable bias for process effects that are not dose based. We have verified that such a capability works with inline processing as the machine writes the mask. The correction was verified on several full reticle curvilinear free-form patterns for EUV using 16nm pixel multibeam writer, the MBM-2000PLUS with the Pixel-Level Dose Correction (PLDC) capability. CD linearity down to 40nm mask features were shown to be within 1nm. As all corrections are performed inline, there is no separate preprocessing step that takes turnaround time (TAT), or explodes the file sizes due to mask process correction. This is a zero TAT solution where files output by ILT and verified by mask rules check (MRC) can be read directly by the mask writer for immediate processing.