Record Details

Investigation of strain in self-assembled multilayer InAs/GaAs quantum dot heterostructures

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Investigation of strain in self-assembled multilayer InAs/GaAs quantum dot heterostructures
 
Creator ADHIKARY, S
HALDER, N
CHAKRABARTI, S
MAJUMDAR, S
RAY, SK
HERRERA, M
BONDS, M
BROWNING, ND
 
Subject 1.3 mu-m
high-temperature operation
chemical-vapor-deposition
infrared photodetector
optical-properties
raman-scattering
gaas
wavelength
relaxation
thickness
nanostructure
molecular beam epitaxy
quantum dots
semiconducting iii-v materials
 
Description The self-assembled InAs/GaAs multilayer quantum dots (QDs) are formed in a strain-driven process due to the lattice mismatch of the InAs/GaAs system. We have investigated strain interaction in 10 layer QD heterostructure with varying thicknesses of combination capping (InAlGaAs and GaAs) by means of scanning transmission electron microscopy (STEM), high-resolution X-ray diffraction (HRXRD) and Raman scattering. STEM micrographs reveal nice stacking of defect-free dots in all the layers of the sample having a thick combination capping. The periodic satellite peaks in the HRXRD rocking curve show good formation of dots and an indication of reduced compressive strain in the heterostructure with increased capping thickness. We detect an upward phonon frequency shift for InAs QDs in the low-temperature Raman study, which is believed to be due to strain relaxation as the thickness of the capping layer increases. The sample with thick combination capping showed better optical emission proper-ties. (C) 2009
 
Publisher ELSEVIER SCIENCE BV
 
Date 2011-07-25T09:22:11Z
2011-12-26T12:50:30Z
2011-12-27T05:35:37Z
2011-07-25T09:22:11Z
2011-12-26T12:50:30Z
2011-12-27T05:35:37Z
2010
 
Type Article
 
Identifier JOURNAL OF CRYSTAL GROWTH, 312(5), 724-729
0022-0248
http://dx.doi.org/10.1016/j.jcrysgro.2009.11.067
http://dspace.library.iitb.ac.in/xmlui/handle/10054/6698
http://hdl.handle.net/10054/6698
 
Language en