Figure 3
From: Nanofocusing of hard X-ray free electron laser pulses using diamond based Fresnel zone plates
Improving the diffraction efficiency of diamond-based Fresnel zone plates.
(a) Overview of the fabrication flow, comprising electron-beam lithography (EBL) to pattern a resist layer, pattern transfer by plasma etching and filling with Ir by atomic layer deposition (ALD). (b) Comparison of a diamond test FZP with 1.2 µm high structures and 100 nm wide outermost zones before and after filling with Ir by atomic layer deposition. The scale bars are 1 µm. (c) Photon energy dependent diffraction efficiencies of a diamond FZP with 1.8 µm high structures and a Ir-filled diamond FZP with 1.2 µm high structures. The solid lines show theoretical efficiency of FZPs made from these materials with the corresponding structure dimensions.
