Electron-beam writing of large-area Fresnel zone plates

High-resolution X-ray microscopy requires advanced fabrication technology for Fresnel zone plates (FZPs). As the resolution of an FZP depends on the width of the outermost zone, fine zone patterns for objective lenses have to be replicated. On the other hand, to achieve highly condensed X-ray beams by using FZPs for condenser lenses, large-field replication is required. A method of pattern replication of FZPs for X-ray microscopy is reported. Utilizing a 30 keV electron-beam writing tool and an FZP-generation computer program, FZP patterns for a condenser lens 1 mm in diameter with an outermost-zone width of 0.2 micro m and for an objective lens 0.5 mm in diameter with an outermost-zone width of 0.1 micro m were replicated.