title: Note: Gratings on low absorbing substrates for x-ray phase contrast imaging.
abstract: Grating based X-ray phase contrast imaging is on the verge of being applied in clinical settings. To achieve this goal, compact setups with high sensitivity and dose efficiency are necessary. Both can be increased by eliminating unwanted absorption in the beam path, which is mainly due to the grating substrates. Fabrication of gratings via deep X-ray lithography can address this issue by replacing the commonly used silicon substrate with materials with lower X-ray absorption that fulfill certain boundary conditions. Gratings were produced on both graphite and polymer substrates without compromising on structure quality. These gratings were tested in a three-grating setup with a source operated at 40 kVp and lead to an increase in the detector photon count rate of almost a factor of 4 compared to a set of gratings on silicon substrates. As the visibility was hardly affected, this corresponds to a significant increase in sensitivity and therefore dose efficiency.
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: F J
authors.initials: FJ
authors.lastname: Koch
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: T J
authors.initials: TJ
authors.lastname: Schröter
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Kunka
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Meyer
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Meiser
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Faisal
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: M I
authors.initials: MI
authors.lastname: Khalil
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, Munich, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Birnbacher
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, Munich, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Viermetz
authors.affiliation: Microworks GmbH, Karlsruhe, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Walter
authors.affiliation: Microworks GmbH, Karlsruhe, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Schulz
authors.affiliation: Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, Munich, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Pfeiffer
authors.affiliation: Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Mohr
mesh_terms: D065638:Absorption, Radiation; D016477:Artifacts; D004867:Equipment Design; D019544:Equipment Failure Analysis; D011829:Radiation Dosage; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation; D014961:X-Ray Diffraction / Q000295:instrumentation*; D014965:X-Rays