Wafer-scale correlated morphology and optoelectronic properties in GaAs/AlGaAs core–shell nanowires

Achieving uniform nanowire size, density, and alignment across a wafer is challenging, as small variations in growth parameters can impact performance in energy harvesting devices such as solar cells and photodetectors. This study demonstrates the in-depth characterization of uniformly grown GaAs/AlGaAs core–shell nanowires on a 2-in. Si(111) substrate using Ga-induced self-catalyzed molecular beam epitaxy. We have developed a method of wafer-scale time correlated single-photon counting with micrometer-resolution and correlate this with scanning electron microscopy to establish a detailed model of structural and optoelectronic properties across the wafer. While emission intensity varies by up to 35%, carrier lifetime shows only 9% variation, indicating stable material quality despite structural inhomogeneities. These findings indicate that, for the 2-in. GaAs/AlGaAs nanowire wafer, achieving uniform nanowire coverage had a greater impact on consistent optoelectronic properties than variations in material quality, highlighting its significance for scalable III–V semiconductor integration on silicon in advanced optoelectronic devices such as solar cells and photodetectors.