Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


Condensed Matter

J. Korean Phy. Soc. 2005; 47(1): 94

Published online July 15, 2005

Copyright © The Korean Physical Society.

Laterally Self-Aligned InGaAs/GaAs Quantum Dots Fabricated by Using a Multilayer Stacking Technique

J. O. Kim, S. J. Lee, S. K. Noh, Y. H. Ryu, S. M. Choi and J. W. Choe


Self-assembled InGaAs/GaAs quantum-dot chains (QDCs) laterally aligned by QDs have been fabricated by using a multilayer stacking technique. In order to investigate the self-aligning behaviors of the QDs induced by the layer stacking, we vary the number of stacks and the growth temperature in the ranges of 1 -- 15 periods and 500 -- 540 $^circ$C, respectively. Atomic force microscope (AFM) images and photoluminescence (PL) spectra reveal that the lateral alignment of QDs is enhanced due to extended length caused by an increased stack period, but severely degrades into film-like wires at temperatures above a critical growth temperature. Introducing an optimized two-step capping procedure, we have demonstrated one-dimensional serpentine QDCs consisting of a single row of coupled QDs whose length is over a few $mu$m and which show strong PL emission at room temperature.