Influence of grain size on direct conversion X-ray sensing Bi2O3 for low-dose X-rays

Low-dose X-ray sensors are essential in healthcare applications, especially for diagnostic and therapeutic pur -poses. The highly sensitive X-ray sensors at low doses are significantly limited by the crystallite morphology of the attenuating materials. Bismuth oxide (Bi2O3) with unique functional properties was used to understand the influence of grain size on direct conversion X-ray induced photocurrent at low dose X-rays (mGy). Hence, a commercial nano-Bi2O3 and bulk-Bi2O3 were developed into a thick film on top of the interdigitated electrode by glass rod sliding technique. The photocurrent instigated for nano-Bi2O3 and bulk-Bi2O3 thick films at different low doses under 3 V biased condition was examined using 70 keV dental X-ray machine. The obtained sensitivity for nanocrystalline Bi2O3 was superior than the bulk-Bi2O3 due to the multiple scattering process, which was discussed in detail.