Ga-In Nanoparticle Induced UV Plasmonic Impact on Heterojunction Based Deep UV Photodetector

Recent developments in Ga ₂ O ₃ -based heterostructures have opened a new area of applications for optoelectronic devices to be used extensively in deep-ultraviolet (UV) photodetection. Although heterostructure has an advantage in the suppression of high dark current, it also reduces the responsivity and photocurrent. In this context, Gallium-Indium (Ga-In) nanoparticles (NPs) have shown local surface plasmon resonance (LSPR) in the UV region and incorporated into n -Ga ₂ O ₃ /p -CuO quasi-heterostructure based deep UV photodetectors (DUPDs) for performance enhancement. An inexpensive jejune electrospinning technique has been used to fabricate the photodetector on a sapphire (0001) substrate. After CuO and Ga ₂ O ₃ layer deposition, sputtering has been used to deposit platinum (Pt) electrodes (50 nm) using a shadow mask. The Ga-In NPs have been drop-casted on top of the fabricated device. The device unveils a dark current of ∼1.03×10 ^-13 A at 5 V . Ga-In NPs induce LSPR that inflicts into a huge electron cloud. Extra electrons generated by LSPR reach the electrodes via the Ga ₂ O ₃ layer and contribute to a very high photocurrent (∼1.14×10 ^-5 A ). Thus, present article illustrates an ultra-low dark current of Ga ₂ O ₃ -based DUPDs with upgraded photo responses by designing a p/n heterojunction with plasmonic NPs.