Figure 6
(a) Pattern of parasitic scattering around the beam stop coming from optics upstream. Diffraction patterns from a carbon membrane of thickness ∼30 nm (b) and a SiN membrane of thickness ∼100 nm (c). S is the scattering vector and defined as S = , where is the diffraction angle and λ is the X-ray wavelength. (d) Typical patterns from cracked membranes. Each pattern is approximated as Fraunhofer diffraction of a narrow slit. Evaluated from the speckle patterns, the width of each slit is estimated to be approximately 90 nm (left panel), 100 nm (center) and 300 nm (right). (e) Diffraction patterns from epoxy membranes with thickness of ∼20 nm (left panel), 100 nm (center) and 200 nm (right). |