Influences of strain and phase separation on the alignment characteristics of five-stacked InAs/lnAIGaAs quantum dots grown on InP(001)

Jin Soo Kim, Cheul Ro Lee, In-Hwan Lee, Jae Young Leem, Joo In Lee, Jong Su Kim

Research output: Contribution to journalArticle

Abstract

This paper reports the influence of the thickness of the InAlGaAs spacer on the formation characteristics of five-stacked In As quantum dots (QDs) grown on InAlGaAs/InP. The emission wavelength for the five-stacked In As QD layers separated by a 5-nm-thick InAlGaAs spacer was 1.526 μm. As the spacer thickness was increased, the emission wavelength was at first red-shifted to 1.550 μm and remained constant thereafter. Also, the carrier lifetime of the In As QDs increased with increasing spacer thickness. The variations in the emission wavelength and in the carrier lifetime with the spacer thickness are most likely due to the change in the QD formation, as confirmed by transmission electron microscopy (TEM). The TEM images indicated that the influence of the accumulation of strain from the bottom QD layer on the formation of the upper QD layer, when a relatively thin spacer was used, was more important than the intrinsic phase separation of InAlGaAs. However, the intrinsic phase separation of the InAlGaAs layer became increasingly dominant as the spacer thickness was increased.

Original languageEnglish
Pages (from-to)1644-1649
Number of pages6
JournalJournal of the Korean Physical Society
Volume54
Issue number4
DOIs
Publication statusPublished - 2009 Apr 1
Externally publishedYes

Keywords

  • Optical properties
  • Quantum dot
  • Structural properties

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Influences of strain and phase separation on the alignment characteristics of five-stacked InAs/lnAIGaAs quantum dots grown on InP(001)'. Together they form a unique fingerprint.

  • Cite this