Deep-ultraviolet photodetector based on pulsed-laser-deposited Cs3Cu2I5 films/n-Si heterojunction

All-inorganic lead-free perovskite C s 3 C u 2 I 5 thin films were prepared using pulsed laser deposition. Effects of the substrate temperature, laser energy, and laser frequency on the film structure and optoelectronic properties were studied. A heterojunction photodetector based on C s 3 C u 2 I 5 / n − S i was constructed, and the deep-ultraviolet photoresponse was obtained. A high I l i g h t / I d a r k ratio of 130 was achieved at − 1.3 V , and the peak response of the heterojunction photodetector was 70.8 mA/W (280 nm), with the corresponding specific detectivity of 9.44 × 10 11 c m ⋅ H z 1 / 2 ⋅ W − 1 . Moreover, the device showed good stability after being exposed to air for 30 days.