Preparation of PbO-Ga2O3 system polycrystalline thin film for direct conversion flexible X-ray detector application

The amorphous bulk PbO-Ga₂O₃ has been demonstrated to possess favorable optoelectronic characteristics for direct X-ray detectors. In this work, a series of PbO-Ga₂O₃ polycrystalline thin films with different gallium atomic percentages were prepared by using electron beam evaporation method. We investigated how the film structure and photoelectric properties vary with gallium content. A direct conversion flexible X-ray detector with a metal/semiconductor/metal (MSM)(30 nm/200 nm/30 nm) structure based on PbO-Ga₂O₃ polycrystalline thin film was fabricated on a polyimide (PI) substrate. The flexible detectors demonstrated an extremely low dark current of only 6.62 pA at 50 V bias voltage, a detection limit of 1.796 nGy/s, and a sensitivity of up to 16.786 × 10³ μC·Gy⁻¹ cm⁻² at an average X-ray energy of 60 keV and an X-ray dose rate of 0.7171 mGy/s. The outcomes of this study demonstrate that PbO-Ga₂O₃ polycrystalline thin films have the potential to be employed as flexible X-ray detection materials.