Highly responsive WO3 based UV-Vis photodetector

The broad range of light detection from ultraviolet to visible has attracted significant attention due to numerous applications like optical communication, spectral switching, and memory storage. Among other semiconductor metal oxides, WO3 is a wide band gap semiconductor with a high optical absorption coefficient (≥104 cm−1), showing great potential in broadband detection. In this report, we have grown tungsten oxide (WO3) film with nano-island surface morphology using the DC magnetron sputtering. The synthesized monoclinic phase of the WO3 film offers a wide bandgap, high stability, and durability, making it suitable for optoelectronic applications. The fabricated metal-semiconductor-metal WO3 photodetector demonstrated a high responsivity of 1.68 AW−1 at 455 nm & 0.39 AW−1 at 355 nm illumination at 2 V applied bias with 4.5 μW optical power. The other figure-of-merits, like external quantum efficiency, noise equivalent power, and detectivity of the developed WO3-based PD were determined as 530 %, 1.31 × 10−12 WHz−1/2, and 5.13 × 1010 Jones for 455 nm & 123 %, 5.61 × 10−12 WHz−1/2, and 1.19 × 1010 Jones for 355 nm, respectively. The study reveals a highly sensitive broadband (UV-Vis) photodetector with superb performance parameters having potential applications in optoelectronics.