Nanoscale-Thick CuPc/beta-Ga2O3 p-n Junctions for Harsh-Environment-Resistant Self-Powered Deep-UV Photodetectors

Due to their crucial role in ultraviolet communication and monitoring, deep-ultraviolet (DUV) photodetectors have garnered much interest. Recently, Ga2O3 has emerged as the best material for DUV photodetectors because of its ultrawide bandgap (4.5-4.9 eV), excellent UV photon absorption coefficient, high structural stability, and affordability. However, there are several difficulties in realizing high-performance Ga2O3- based DUV photodetectors with a high tolerance for harsh environments. In this work, nanoscale-thick CuPc/beta-Ga2O3 p-n junctions were used to build high-performance DUV photodetectors by a straightforward solution-processing approach. The p-n junction photodetectors exhibit improved photoelectric performance compared to a single device made of beta-Ga2O3 or CuPc, with a photo-to dark current ratio of 3700 and a fast response time of similar to 20 ms under a bias of 0 V. Due to the excellent stability of the nanoscalethick CuPc film, the device can maintain a high photocurrent even at high temperatures or under long-term DUV irradiation. Our work provides an effective strategy toward highly harsh-environment-resistant DUV photodetectors.