Soft x-ray lenses with 400 A outer zone width for nanostructure imaging

Fresnel zone plate lenses designed for imaging and microscopy at soft x-ray wavelengths have been fabricated with outer zone widths of 400 A. The zone plates were fabricated by electron beam lithography using a high resolution vector scan system designed specifically for nanometer pattern writing and equipped with high speed polar to cartesian converter for circular pattern generation. Gold electroplating was used to form the absorber pattern. Special measures taken to assure pattern fidelity will be described.