High-performance direct conversion X-ray detectors based on sintered hybrid lead triiodide perovskite wafers

摘要

Lead halide perovskite semiconductors are in general known to have an inherently high X-ray absorption cross-section and a significantly higher carrier mobility than any other low-temperature solution-processed semiconductor. So far, the processing of several-hundred-micrometres-thick high-quality crystalline perovskite films over a large area has been unresolved for efficient X-ray detection. In this Article, we present a mechanical sintering process to fabricate polycrystalline methyl ammonium lead triiodide perovskite (MAPbI(3)) wafers with millimetre thickness and well-defined crystallinity. Benchmarking of the MAPbI(3) wafers against state-of-the-art CdTe detectors reveals competitive conversion efficiencies of 2,527 mu C Gy(air)(-1) cm(-2) under 70 kV(p) X-ray exposure. The high ambipolar mobility-lifetime product of 2 x 10(-4) cm(2) V-1 is suggested to be responsible for this exceptionally high sensitivity. Our findings inform a new generation of highly efficient and low-cost X-ray detectors based on perovskite wafers.