  X-ray photon detection is important for a wide range of applications. The
highest demand, however, comes from medical imaging, which requires
cost-effective, high-resolution detectors operating at low photon flux,
therefore stimulating the search for novel materials and new approaches.
Recently, hybrid halide perovskite CH3NH3PbI3 (MAPbI3) has attracted
considerable attention due to its advantageous optoelectronic properties and
low fabrication costs. The presence of heavy atoms, providing a high scattering
cross-section for photons, makes this material a perfect candidate for X-ray
detection. Despite the already-successful demonstrations of efficiency in
detection, its integration into standard microelectronics fabrication processes
is still pending. Here, we demonstrate a promising method for building X-ray
detector units by 3D aerosol jet printing with a record sensitivity of 2.2 x
108 {\mu}C Gyair-1cm-2 when detecting 8 keV photons at dose-rates below 1 Gy/s
(detection limit 0.12 Gy/s), a four-fold improvement on the best-in-class
devices. An introduction of MAPbI3-based detection into medical imaging would
significantly reduce health hazards related to the strongly ionizing X-rays
photons.
