Two-Dimensional InGaAs Quantum-Dot Arrays with Periods of 70-100 nm on Artificially Prepared Nanoholes

Abstract

We have fabricated two-dimensional InGaAs quantum-dot (QD) arrays with periods of 70 nm and 100 nm, where the nucleation probability of QDs reached ∼100%. This regular QD array was realized by controlling the nucleation sites on artificially prepared nanohole arrays on GaAs (001) substrates using low-temperature deposition of In0.33Ga0.67As and subsequent annealing. On the regular QD array with the 100 nm periodicity, three InGaAs QD layers were stacked. A cross-sectional image of the stacked sample revealed vertical alignment of the QDs, which showed a clear photoluminescence peak at room temperature.