Enhanched UV photodetector based on WO3/SnO2 heterostructure nanowire

Abstract

WO₃/SnO₂ heterostructure nanowire array was fabricated using the Glancing angle deposition technique (GLAD), which is a growth-controlled and catalytic-free process. Well-aligned, vertical NWs are observed in the field emission scanning electron microscope image. The X-ray diffraction measurement revealed SnO₂ amorphous and WO₃ crystalline nature. The material exhibits strong absorption in the UV region with a direct bandgap of approximately 3.1 eV and 3.6 eV for WO₃ and SnO_2, respectively. Electrical analysis at room temperature, conducted over a voltage range of -5 to 5 V, demonstrates the device's performance, with a good detectivity (D*) of 6.93 × 10¹³ and responsivity of 5.9 A/W. Additionally, the device shows a stable switching response at -3 V, with a rise time of 0.30 s and a fall time of 0.32 s.