2025/02/12 by Yury Berdnikov, Berdnikov, Yury, Paweł Holewa +17 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Optics (physics.optics) #Photonic Crystals and Applications #Photonic and Optical Devices #Silicon Nanostructures and Photoluminescence
paper · pdf · doi:10.48550/arxiv.2502.08616
openalex publication_date 2025/02/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Surface effects can significantly impact the performance of nanophotonic and quantum photonic devices, especially as the device dimensions are reduced. In this work, we propose and investigate a novel approach to surface passivation to mitigate these challenges in photonic nanostructures with III-As(P) quantum wells defined by a dry etching process. The nanostructures are annealed under the phosphine (PH3) ambient inside a metal-organic vapor phase epitaxy chamber to eliminate surface and subsurface defects induced during the dry etching and subsequent oxidation of the etched sidewalls. Moreover, encapsulation of the active material with a wider bandgap material allows for maintaining the band structure of the device, mitigating band bending effects. Our findings reveal an almost order of magnitude reduction in the surface recombination velocity from 2 × 103 cm/s for the PH3 annealing compared to 1.5 × 104 cm/s for the non-passivated structures and 5 × 103 cm/s for the standard method based on (NH4)2S wet treatment followed by Al2O3 encapsulation. A further reduction to 5 × 102 cm/s is achieved for the InP-regrown samples. Additionally, we develop a model accounting for the impact of surface charges in the analysis of time-resolved photoluminescence curves and demonstrate that the proposed passivation method effectively reduces the surface charge density on the sidewalls of the studied quantum well-based photonic nanostructures.