Advanced Organic-Inorganic Hybrid Solar-Blind UV Photodetector With β-Ga₂O₃ Film From Thermal Oxidation

In this article, a simple and reproducible technology combining one-step thermal oxidation and the spraying method is presented for fabricating the high-performance organic-inorganic hybrid solar-blind ultraviolet (SBUV) photodetector (PD).
$\beta $
-Ga2O3/GaN het- erojunction is readily built by the one-step thermal oxidation and sprayed with organic transparent conductive PEDOT:PSS to finish the construction of PEDOT:PSS/
$\beta $
-Ga2O3/GaN organic-inorganic hybrid heterojunction devices. Here, the optimal dosage of PEDOT:PSS is determined as 2 mL by balancing its SBUV transmittance and conductivity. The optimized device constructed with this 2 mL PEDOT:PSS exhibits a high photoresponsivity of 8.52 mA/W, a fast response with a decay time of 40.7 ms, and an SBUV-UV injection ratio (
${R}_{\text {258 nm/365 nm}}$
) over three orders of magnitude under 0 V bias and SBUV light irradiation. In addition, the feasibility of using PEDOT:PSS/
$\beta $
-Ga2O3/GaN SBUV PD as an optical receiver for secure SBUV communication systems encrypted by international Morse code has been verified. The low-cost and high-efficiency synthesis of gallium oxide as well as the preparation of organic-inorganic hybrid SBUV PDs proposed in this study can provide a new reference for the large-scale production of
$\beta $
-Ga2O3-based high-performance heterojunction SBUV photovoltaic (PV) PDs.