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arXiv · 2501.13441

Ordered InAs QDs using prepatterned substrates by monolithically integrated porous alumina

Pablo Alonso-González·María S. Martín-González·Javier Martín-Sánchez·Yolanda González·Luisa González
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Abstract

In this work, we explore a method for obtaining site-controlled InAs quantum dots (QDs) on large areas of GaAs (0 0 1) pre-patterned surface. The patterning of the substrate is obtained by using a monolithically integrated nano-channel alumina (NCA) mask and transferring its self-ordering to the underlying GaAs substrate by continuing the anodization process once the GaAs surface is reached. After patterning, the GaAs substrate follows a low temperature process for surface preparation before epitaxial growth for QD formation. As a final result, we observe that the nanoholes act as preferential nucleation sites for InAs QD formation, with a filling factor close to unity, while the QD formation on the surface region between the pattern holes is completely suppressed.

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Pablo Alonso-González, María S. Martín-González, Javier Martín-Sánchez, Yolanda González, Luisa González. 2025-01-23. Ordered InAs QDs using prepatterned substrates by monolithically integrated porous alumina. https://doi.org/10.1016/j.jcrysgro.2006.06.012

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