Reflection zone plates

At the FG-ANT wide variety of reflection zone plates are made. Since these zone plates are used as the dispersing optical element, only a part of the zone plate is used (off-axis).

Typical RZP geometry as the dispersing element

To get an impression of how the zone plates are prepared, here the typical manufacturing steps are shown:

1. Applying a positive e-beam resist
2. Exposure to a electron beam writer
3. Development of the resist
4. Reactive ion etching in the silicon substrate
5. Detachment of the resist
6. Coating with (typically) gold