30 nm resolution x-ray imaging at 8 keV using third order diffraction of a zone plate lens objective in a transmission microscope

A hard x-ray transmission microscope with 30 nm spatial resolution has been developed employing the third diffraction order of a zone plate objective. The microscope utilizes a capillary type condenser with suitable surface figure to generate a hollow cone illumination which is matched in illumination range to the numerical aperture of the third order diffraction of a zone plate with an outmost zone width of 50 nm. Using a test sample of a 150 nm thick gold spoke pattern with finest half-pitch of 30 nm, the authors obtained x-ray images with 30 nm resolution at 8 keV x-ray energy.