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arXiv · 2501.12455

Self-assembling of Ge quantum dots in an alumina matrix

M. Buljan·S. R. C. Pinto·A. G. Rolo·J. Martín-Sánchez·M. J. M. Gomes·J. Grenzer·A. Mücklich·S. Bernstorff·V. Holý
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Abstract

In this work we report on a self-assembled growth of a Ge quantum dot lattice in a single 600-nm-thick Ge+Al2O3 layer during magnetron sputtering deposition of a Ge+Al2O3 mixture at an elevated substrate temperature. The self-assembly results in the formation of a well-ordered threedimensional body-centered tetragonal quantum dot lattice within the whole deposited volume. The quantum dots formed are very small in size less than 4.0 nm, have a narrow size distribution and a large packing density. The parameters of the quantum dot lattice can be tuned by changing the deposition parameters. The self-ordering of the quantum dots is explained by diffusionmediated nucleation and surface-morphology effects and simulated by a kinetic Monte Carlo model.

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M. Buljan, S. R. C. Pinto, A. G. Rolo, J. Martín-Sánchez, M. J. M. Gomes, J. Grenzer, A. Mücklich, S. Bernstorff, V. Holý. 2025-01-21. Self-assembling of Ge quantum dots in an alumina matrix. https://doi.org/10.1103/physrevb.82.235407

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