A High Responsivity and Photosensitivity Self‐Powered UV Photodetector Constructed by the CuZnS/Ga₂O₃ Heterojunction

Abstract Fabricating a heterojunction photodetector is efficient to take advantage of the built‐in electric field formed by heterojunction and thus improve the performance of photodetector. Herein, a CuZnS/Ga 2 O 3 type‐II heterojunction photodetector is designed and constructed by chemical bath deposition for the first time. The photodetector exhibits super high rectifying characteristics (5.7 × 10 4 at ± 1 V), high responsivity (48.01 mA W −1 at 0 V), and detectivity (1.83 × 10 12 Jones at 0 V), which are higher than most of the reported inorganic devices as far as the authors know. Benefiting from built‐in electric field constructed by the CuZnS/Ga 2 O 3 type‐II heterojunction, the photo‐induced electron and hole pairs are quickly separated by the built‐in electric field between the Ga 2 O 3 and the CuZnS interface. Therefore, the photodetector constructed by CuZnS/Ga 2 O 3 type‐II heterojunction shows a prominent self‐powered performance. At zero bias, the photodetector shows a fast photoresponse (rise time τ r = 70 ms, decay time τ d = 10 ms). These data of performance are significantly excellent to most of the reported Ga 2 O 3 heterojunction photodetectors. These performances strongly suggest that the CuZnS/Ga 2 O 3 photodetector has great potential in ultra‐high performance self‐powered solar‐blind photodetector.