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arXiv · 2501.05275

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

Ishika Das·Keisuke Minehisa·Fumitaro Ishikawa·Patrick Parkinson·Stephen Church
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Abstract

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 like solar cells and photodetectors. This study demonstrates the in-depth characterization of uniformly grown GaAs/AlGaAs core-shell nanowires on a two-inch Si(111) substrate using Ga-induced self-catalyzed molecular beam epitaxy. By integrating Scanning Electron Microscopy and Time Correlated Single-Photon Counting, we establish a detailed model of structural and optoelectronic properties across wafer and micron scales. 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 two-inch 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.

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Ishika Das, Keisuke Minehisa, Fumitaro Ishikawa, Patrick Parkinson, Stephen Church. 2025-01-09. Wafer-scale correlated morphology and optoelectronic properties in GaAs/AlGaAs core-shell nanowires. https://arxiv.org/abs/2501.05275

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