【Device Papers】High-performance, energy-efficient graphene/Ga₂O₃ heterojunction solar-blind photodetectors enhanced by carrier- carrier scattering

      Researchers from the Fuzhou University have published a dissertation titled "High-performance, energy-efficient graphene/Ga₂O₃ heterojunction solar-blind photodetectors enhanced by carrier- carrier scattering" in Optics & Laser Technology.

Abstract

      Conventional Ga₂O₃-based solar-blind photodetectors typically require a high bias voltage for efficient operation, leading to significant energy consumption. To address this, we propose an alternative approach using MOCVD-grown homoepitaxial β-Ga₂O₃ thin films on (100) Sn-doped β-Ga₂O₃ wafer to develop photodetectors with ultra-low bias and high gain. A graphene/ Ga₂O₃ heterojunction device was fabricated, exhibiting an exceptionally low dark current of 0.1nA and a photocurrent ratio of 10⁴ at −5 V, along with a suppression ratio (R_254nm/R_405nm) of 1800 at 0 V. By leveraging graphene’s carrier-carrier scattering and Ga₂O₃′s UV absorption, the device achieved a responsivity increase from 0.04 mA/W (0 V) to 30 mA/W (−0.5 V), equivalent to a 73944 % enhancement, while the detectivity improved by 1096 %, reaching 2.68 × 10¹² Jones. This work provides insights into the development of highly sensitive, low-power solar-blind UV photodetectors.

DOI：

https://doi.org/10.1016/j.optlastec.2025.113525