Solution Spin-Coated BiFeO₃ Onto Ga₂O₃ Towards Self-Powered Deep UV Photo Detector of Ga₂O₃/BiFeO₃ Heterojunction

Abstract

Ga ₂ O ₃ is one of the most suitable semiconductor materials for performing deep UV photoelectric detection. In this work, a self-powered deep UV photodetector based on a Ga ₂ O ₃ /BFO heterojunction is fabricated via solution spin-coating and metal-organic chemical vapor deposition (MOCVD) methods. Without biasing driven, the device achieves an extreme low dark current ( ${I}_{dark}$ ) of 8.38 fA, a photo-to-dark current ratio ( PDCR ) of $1.66\times10$ ⁵ , a high specific detectivity ( ${D} \ast $ ) of $6.1\times 10^{12}$ Jones and an open-circuit voltage ( ${V}_{\textit {oc}}$ ) of 0.55 V responding to deep UV irradiation (254 nm in this work). Through analyzing the band diagram of the heterojunction, the intrinsic physical characteristics of the photodetector are discussed. Results show that the photodetector has excellent deep UV signal detecting ability, indicating that Ga ₂ O ₃ /BFO heterojunction is a potential candidate for performing self-powered deep UV photodetection.