Antimony incorporation in InAs quantum dots grown on GaAs substrate by molecular beam epitaxy

✍ Scribed by J. Rihani; V. Sallet; H.J. Christophe; M. Oueslati; R. Chtourou

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 272 KB
• Volume: 40
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/j.physe.2007.08.059

✦ Synopsis

We have grown InAs(Sb) quantum dots (QDs) on GaAs (0 0 1) substrates by molecular beam epitaxy (MBE) using two different antimony exposures (F Sb ). Atomic force microscopy (AFM) and photoluminescence (PL) spectroscopy were carried out to investigate the dot size evolution as function of the incorporated antimony content in InAs/GaAs QDs material. Anomalous asymmetric-band feature was observed in room temperature photoluminescence (RTPL) spectra of the investigated QD samples grown at relatively high temperature (490 1C). From the temperature-dependent PL measurements, it was found that the asymmetric-band feature is associated with the ground-states transitions from QDs with bimodal size distribution. The analysis of the pump power dependent PL spectra allows us to suggest a type II band lineup for the InAsSb/GaAs QDs materials system.