Replication of near 0.1 μm hole patterns by using x‐ray lithography

The feasibility of x‐ray lithography in applying device process was studied through fabrication of a small circuit consisting of experimental stacked film and contact holes numbering about 1k with replicated sizes from 0.6 to 0.085 μm. To resolve fine contact holes, in‐house chemically amplified positive resist was used by employing a high contrast post‐exposure‐bake condition. By measuring the resistance and yields of prepared circuits, we have evaluated the reliability of the circuits. High yield of larger than 0.9 was obtained for contact holes larger than 0.15 μm, and prepared circuits were found to be feasible down to 0.085 μm.