Capability of 70 nm pattern replication in x-ray lithography

It has been shown that the Proximity X-ray Lithography (PXL) is the most mature technology among Next Generation Lithography (NGL) options at 100 nm node. As the basic resolution of PXL is defined by the Fresnel diffraction, sub-100 nm patterns are resolved if only the Mask-to-Wafer gap is set properly. Resolution of 65 nm L/S patterns with a gap of 10 /spl mu/m was demonstrated. Recently, the limit of optical lithography is expected to extend to deep sub-100 nm using the F/sub 2/ laser lithography. However the advantage of PXL to F/sub 2/ at 70 nm node was shown in calculation. In this study some experimental results for 70-nm node pattern replication are shown and discussed.