Electronic Transport in AlGaN/GaN Nanowires Under Ultraviolet Excitation and Edge Depletion Effect, Studied in a Wide Temperature Range

ABSTRACT Gallium nitride (GaN) nanowires are promising for nanoelectronic and biosensing applications due to their unique electronic properties and stability. However, understanding electron transport in AlGaN/GaN nanowires, particularly the influence of edge depletion and trap states, remains limited. Here, we investigate electronic transport in AlGaN/GaN transistor‐like heterostructures patterned into nanowires of varying widths (185–1110 nm), analyzing current–voltage characteristics under dark and ultraviolet (UV) illumination. External UV excitation influences the depletion widths in NWs, modulates space‐charge‐limited current (SCLC), and provides information about the distribution range of traps in NW structures. We observe a transition from Ohmic to SCLC regimes, with UV excitation modulating depletion widths and enhancing conductivity by releasing trapped carriers. Temperature‐dependent measurements allow us to estimate trap energy distributions in the range of 150–200 meV, confirmed by noise spectroscopy data. These findings demonstrate that optical excitation effectively controls SCLC transport in GaN nanowires, offering insights for designing sensitive nanoelectronic and biosensing devices leveraging trap‐mediated charge dynamics.