Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


J. Korean Phy. Soc. 2008; 53(4): 2100-2104

Published online October 15, 2008

Copyright © The Korean Physical Society.

Photoluminescence Characteristics of Self-Aligned InGaAs Quantum Dots Fabricated by Using Atomic Layer Epitaxy

J. O. Kim, S. J. Lee, S. K. Noh, J. W. Choe and T. W. Kang


We report the structural and the photoluminescence (PL) characteristics of spontaneously aligned InGaAs/GaAs quantum dots (QDs) that are self-assembled by using atomic layer epitaxy (ALE). Atomic force microscopy clearly identified that isolated QDs became more closely coupled and spontaneously aligned to a one-dimensional chain-like structure by simply increasing the nominal InGaAs coverage with no introduction of multiple layer stacking. The asymmetric PL spectra were analyzed by using a superposition of two main contributions due to different QD modes and the strong redshift behavior observed in the temperature dependence might be attributed to a distinctive property in very closely coupled ALE-grown QDs that is due to carrier tunneling occurring in company with thermal carrier transfer.

Keywords: Self-aligned quantum dots, Indium gallium arsenide, Atomic layer epitaxy, Atomic force microscopy, Photoluminescence