Fresnel zone plates made by holography in the extreme ultraviolet region

We present the fabrication of Fresnel zone plates (FZP) by holography that yields FZPs completely free from imperfections such as zone placement errors and finite pixel size effects found in serial writing techniques such as e-beam lithography (EBL). Our holographic scheme is based on the interference of a spherical wave and a plane wave. A partially transparent membrane containing a pinhole is illuminated by a fully coherent plane wave (lambda=13.4 nm). The spherical wave, obtained by diffraction from the pinhole, interferes with the plane reference wave that is transmitted by the membrane. The interference pattern, which is a hologram of the pinhole, is recorded on a photoresist film and used to fabricate a FZP that has resolution similar to the size of the pinhole.