【Member Papers】Nanjing University of Posts and Telecommunications——Self-powered PEDOT:PSS/Sn:α-Ga₂O₃ heterojunction UV photodetector via organic/inorganic hybrid ink engineering

      Researchers from the Nanjing University of Posts and Telecommunications have published a dissertation titled "Self-powered PEDOT:PSS/Sn:α-Ga₂O₃ heterojunction UV photodetector via organic/inorganic hybrid ink engineering" in Journal of Semiconductors.

Abstract

      In this work, a PEDOT:PSS/Sn:α-Ga₂O₃ hybrid heterojunction diode (HJD) photodetector was fabricated by spin-coating highly conductive PEDOT:PSS aqueous solution on the mist chemical vapor deposition (Mist-CVD) grown Sn:α-Ga₂O₃ film. This approach provides a facile and low-cost p-PEDOT:PSS/n-Sn:α-Ga₂O₃ spin-coating method that facilitates self-powering performance through p−n junction formation. A typical type-Ⅰ heterojunction is formed at the interface of Sn:α-Ga₂O₃ film and PEDOT:PSS, and contributes to a significant photovoltaic effect with an open-circuit voltage (V_oc) of 0.4 V under the 254 nm ultraviolet (UV) light. When operating in self-powered mode, the HJD exhibits excellent photo-response performance including an outstanding photo-current of 10.9 nA, a rapid rise/decay time of 0.38/0.28 s, and a large on/off ratio of 91.2. Additionally, the HJD also possesses excellent photo-detection performance with a high responsivity of 5.61 mA/W and a good detectivity of 1.15 × 10¹¹ Jones at 0 V bias under 254 nm UV light illumination. Overall, this work may explore the potential range of self-powered and high-performance UV photodetectors.

Fig. 1. (a) Experimental procedures of the Mist-CVD. (b) Fabrication process of the HJD−PD.

Fig. 2.  Optical absorbance spectra of (a) PEDOT:PSS film and (b) Sn:α-Ga₂O₃ film (the inset calculates the E_g of the Sn:α-Ga₂O₃ film). (c) XRD pattern of Sn:α-Ga₂O₃.

DOI： 

doi.org/10.1088/1674-4926/24050048