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/Ga2O3 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 × 104 at ± 1 V), high responsivity (48.01 mA W−1 at 0 V), and detectivity (1.83 × 1012 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/Ga2O3 type-II heterojunction, the photo-induced electron and hole pairs are quickly separated by the built-in electric field between the Ga2O3 and the CuZnS interface. Therefore, the photodetector constructed by CuZnS/Ga2O3 type-II heterojunction shows a prominent self-powered performance. At zero bias, the photodetector shows a fast photoresponse (rise time τr = 70 ms, decay time τd = 10 ms). These data of performance are significantly excellent to most of the reported Ga2O3 heterojunction photodetectors. These performances strongly suggest that the CuZnS/Ga2O3 photodetector has great potential in ultra-high performance self-powered solar-blind photodetector.