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arXiv · 1007.1579

Growth and structural characterization of pyramidal site-controlled quantum dots with high uniformity and spectral purity

Valeria Dimastrodonato·Lorenzo O. Mereni·Robert J. Young·Emanuele Pelucchi
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Abstract

This work presents some fundamental features of pyramidal site-controlled InGaAs Quantum Dots (QDs) grown by MetalOrganic Vapour Phase Epitaxy on patterned GaAs (111)B substrate. The dots self-form inside pyramidal recesses patterned on the wafer via pre-growth processing. The major advantage of this growth technique is the control it provides over the dot nucleation posi-tion and the dimensions of the confined structures onto the sub-strate. The fundamental steps of substrate patterning and the QD forma-tion mechanism are described together with a discussion of the structural particulars. The post-growth processes, including sur-face etching and substrate removal, which are required to facili-tate optical characterization, are discussed. With this approach extremely high uniformity and record spectral purity are both achieved.

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Valeria Dimastrodonato, Lorenzo O. Mereni, Robert J. Young, Emanuele Pelucchi. 2010-07-09. Growth and structural characterization of pyramidal site-controlled quantum dots with high uniformity and spectral purity. https://doi.org/10.1002/pssb.200983803

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