TY - JOUR
T1 - Emission and HR-XRD study of MBE structures with InAs quantum dots and AlGaInAs strain reducing layers
AU - Torchynska, T.
AU - Cisneros-Tamayo, R.
AU - Vega-Macotela, L.
AU - Polupan, G.
AU - Escobosa-Echavarria, A.
N1 - Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/12
Y1 - 2018/12
N2 - GaAs/Al0.30Ga0.70As quantum wells (QWs) with InAs quantum dot (QD) arrays covered by the different capping layers: Al0.30Ga0.70As or Al0.1Ga0.75In0.15As, have been investigated by means of the photoluminescence (PL) and high resolution X-ray diffraction (HR-XRD) methods. It is revealed that the QD emission in the structure with Al0.1Ga0.75In0.15As capping is characterized by the lower PL energy, higher PL intensity of ground state emission and smaller its full width at half maximum (FWHM) in comparison with ground state QD emission at Al0.30Ga0.70As capping. The analysis of PL and HR-XRD scans has shown that the strain relaxation at high QW growth temperatures in the structure with Al0.30Ga0.70As capping was connected with changing significantly the material compositions of the QDs and capping layer. As a result the QD emission shifts into the higher energy range, the PL intensity decreases and the FWHMs of PL bands increase. In contrary, in the structure with Al0.1Ga0.75In0.15As capping the strain relaxation manifests itself by decreasing the InAs QD heights without changing the InAs QD material composition. The advantage of Al0.1Ga0.75In0.15As capping has been discussed.
AB - GaAs/Al0.30Ga0.70As quantum wells (QWs) with InAs quantum dot (QD) arrays covered by the different capping layers: Al0.30Ga0.70As or Al0.1Ga0.75In0.15As, have been investigated by means of the photoluminescence (PL) and high resolution X-ray diffraction (HR-XRD) methods. It is revealed that the QD emission in the structure with Al0.1Ga0.75In0.15As capping is characterized by the lower PL energy, higher PL intensity of ground state emission and smaller its full width at half maximum (FWHM) in comparison with ground state QD emission at Al0.30Ga0.70As capping. The analysis of PL and HR-XRD scans has shown that the strain relaxation at high QW growth temperatures in the structure with Al0.30Ga0.70As capping was connected with changing significantly the material compositions of the QDs and capping layer. As a result the QD emission shifts into the higher energy range, the PL intensity decreases and the FWHMs of PL bands increase. In contrary, in the structure with Al0.1Ga0.75In0.15As capping the strain relaxation manifests itself by decreasing the InAs QD heights without changing the InAs QD material composition. The advantage of Al0.1Ga0.75In0.15As capping has been discussed.
KW - AlGaInAs strain reducing layer
KW - HR-XRD
KW - InAs QDs
KW - Photoluminescence
UR - http://www.scopus.com/inward/record.url?scp=85055989498&partnerID=8YFLogxK
U2 - 10.1016/j.spmi.2018.10.005
DO - 10.1016/j.spmi.2018.10.005
M3 - Artículo
SN - 0749-6036
VL - 124
SP - 153
EP - 159
JO - Superlattices and Microstructures
JF - Superlattices and Microstructures
ER -