Characteristics of A Hybrid Detector Combined with A Perovskite Active Layer for Indirect X-ray Detection

• Main Authors: Hailiang Liu, Jehoon Lee, Jungwon Kang
• Format: Article
• Language: English
• Published: MDPI AG 2020-12-01
• Series: Sensors
• Subjects: perovskite active layer; indirect X-ray detector; hybrid detector
• Online Access: https://www.mdpi.com/1424-8220/20/23/6872

In this study, we investigated the characteristics of an organic-inorganic hybrid indirect-type X-ray detector with a CH₃NH₃PbI₃ (MAPbI₃) perovskite active layer. A layer with a thickness of 192 nm annealed at 100 °C showed higher absorption, higher crystallinity, and lower surface roughness than did perovskite layers made under different conditions. In the indirect X-ray detector, a scintillator coupled with the detector to convert X-ray photons to visible photons, and the converted photons were absorbed by the active layer to generate charge carriers. The detector with the optimized MAPbI₃ (192 nm thick and 100 °C annealing condition) active layer was coupled with a CsI(Tl) scintillator which consisted of 400 μm thick CsI and 0.5 mm thick Al, and achieved the highest sensitivity, i.e., 2.84 mA/Gy·cm². In addition, the highest short-circuit current density (J_SC), i.e., 18.78 mA/cm², and the highest mobility, i.e., 2.83 × 10⁻⁴ cm²/V·s, were obtained from the same detector without the CsI(Tl) scintillator.