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

Abstract
A hard x-ray transmission microscope with 30nm 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 50nm. Using a test sample of a 150nm thick gold spoke pattern with finest half-pitch of 30nm, the authors obtained x-ray images with 30nm resolution at 8keV x-ray energy.