Small-Area Perovskite Photodiodes With High Detectivity and Stability

Small-area perovskite photodiodes with an active area of 50 μm × 50 μm are achieved, showing both high specific detectivity and excellent stability. The device exhibits a low dark current density of ~ 1.6×10 ^-8 A/cm ² at a reverse bias of 0.1 V, a peak photoresponsivity of 1.74 A/W, and a peak specific detectivity of 1.5×10 ¹³ Jones. Moreover, the device also shows superior photoresponse and thermal stability after continuous 1000 cycles of light switching and 400 h of thermal aging at 85 °C. The high performance is ascribed to the blocking of minority carrier injection from electrodes under a reverse bias and the high crystal quality and thermal stability of the CH ₃ NH ₃ (MA)-free perovskite photoactive layer.