Mask gate CD variations reduced with double-step maskmaking

摘要

We have clearly shown a double-step process using available reticle fabrication tools, for example the ALTA 3500, which exhibited sufficient overlay capability. Our technique can reduce CD variation of gate lines on the poly-layer reticle, confirming our belief that the double-step process is a concrete method to meet the reticle CD uniformity required in low-k{sub}1 lithography.