Engineered Optical and Electronic Properties in β-Ga₂O₃/SnO₂ Nanowire Networks.

Abstract

Integration of semiconductor nanowires is critical for developing scalable and versatile nanodevices, but challenges remain in tailoring optical emission, forming reliable p-n junctions, and ensuring consistent nanoscale interconnection. Here, we investigate Ga₂O₃/SnO₂ multiwire architectures using synchrotron-based X-ray fluorescence (XRF), X-ray excited optical luminescence (XEOL), X-ray absorption near-edge spectroscopy (XANES), and first-principles simulations. We map dopant distribution, analyze nanoscale optical responses, and determine dopant atomic coordination. The central wire is predominantly Sn-doped Ga₂O₃, while crossed wires are Ga-doped SnO₂. XEOL maps reveal a pronounced enhancement of the 3.5 eV ultraviolet emission in Ga₂O₃ at the junctions, enabling controlled optical modulation. XANES and <i>ab initio</i> calculations confirm that Sn and Ga dopants preferentially occupy octahedral sites, introducing donor levels in Ga₂O₃ and acceptor levels in SnO₂. This research significantly advances our understanding of dopant effects in complex semiconductor nanowire systems, paving the way for controlled optical emissions in Ga₂O₃/SnO₂ multiwire architectures.