Optimization of resolution-enhanced photolithography for a 256 Mb DRAM cell

An approach for design-specific lithography optimization using simulation and experimental validation has been demonstrated for a 256 Mb DRAM cell. Results from this study indicate that the optimum lithographic solution has a strong dependence on pattern shape and density. Initial emphasis in the implementation of resolution-enhancement techniques should be placed on the development of attenuated phase-shifting masks as well as off-axis illumination. These efforts must continue to strive towards extending lithographic performance beyond current capabilities at 0.25 /spl mu/m groundrules.<
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