【Domestic Papers】Enhanced Performance of Gallium-Based Wide Bandgap Oxide Semiconductor Heterojunction Photodetector for Solar-Blind Optical Communication via Oxygen Vacancy Electrical Activity Modulation

      Researchers from the Zhejiang Sci-Tech University have published a dissertation titled "Enhanced Performance of Gallium-Based Wide Bandgap Oxide Semiconductor Heterojunction Photodetector for Solar-Blind Optical Communication via Oxygen Vacancy Electrical Activity Modulation " in Advanced Optical Materials.

Abstract

      Gallium oxide (β-Ga₂O₃) is a prominent representative of the new generation of wide-bandgap semiconductors, boasting a bandgap of ≈4.9 eV. However, the growth process of β-Ga₂O₃ materials introduces unavoidable oxygen vacancies (Vo), leading to persistent photoconductivity (PPC), a phenomenon that severely hinders device performance. In this study, an innovative approach is successfully developed by introducing high p-orbital energy nitrogen (N). This leads to the formation of a hybridized state with O 2p orbitals in β-Ga₂O₃, resulting in the creation of GaON and suppressing the electrical activity of Vo. Through meticulous experimentation and advanced computational methods, a comprehensive and insightful explanation of the regulation and mechanism underlying this passivation process is offered. Moreover, pn-junction solar-blind photodetectors are engineered using hybridized GaON thin films with p-type CuPc. These photodetectors demonstrate exceptional characteristics, including ultra-low dark current (10⁻¹⁴ A), high photo-to-dark current ratio (10⁶), and rapid decay speed (0.008 s) even at zero bias. Based on these advancements, a solar-blind ultraviolet communication system is designed, featuring straightforward and reliable encoding, easy implementation, and robust anti-interference capabilities.

Paper Link：https://doi.org/10.1002/adom.202302294