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

TL;DR

This paper investigates the growth and structural features of pyramidal site-controlled InGaAs quantum dots, demonstrating high uniformity and spectral purity through a controlled epitaxial process on patterned substrates.

Contribution

It introduces a method for growing highly uniform, spectrally pure quantum dots with precise control over their position and size using MetalOrganic Vapour Phase Epitaxy on patterned GaAs substrates.

Findings

Achieved record spectral purity of quantum dots.

Demonstrated high uniformity in quantum dot size and position.

Controlled nucleation and formation of quantum dots within pyramidal recesses.

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.