Photoluminescence and Raman analysis of strain and composition in InGaAs/AlGaAs pseudomorphic heterostructures
J M Gilperez; F Gonzalez-Sanz; E Calleja; E Munoz; J M Calleja; N Mestres; J Castagne; E Barbier; J M Gilperez; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; F Gonzalez-Sanz; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; E Calleja; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; E Munoz; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; J M Calleja; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; N Mestres; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; J Castagne; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain; E Barbier; ETSI Telecomunicacion, Univ. Politecnica, Madrid, Spain
Журнал:
Semiconductor Science and Technology
Дата:
1992-04-01
Аннотация:
Photoluminescence and Raman spectroscopy have been used to determine composition and strain in pseudomorphic In<sub>x</sub>Ga<sub>1-x</sub>As/Al<sub>x</sub>Ga<sub>1-y</sub>As quantum wells. Series of MBE-grown samples, comprising bulk-relaxed In<sub>x</sub>Ga<sub>1-x</sub>As reference layers and In<sub>x</sub>Ga<sub>1-x</sub>As/Al<sub>y</sub>Ga<sub>1-y</sub>As quantum wells of different thicknesses, were considered. Photoluminescence transitions in the strained structures were analysed using a semiempirical model including strain and composition effects in the In<sub>x</sub>Ga<sub>1-x</sub>As well. The GaAs-like longitudinal optical LO phonon Raman shift allowed an independent strain estimation. The agreement between photoluminescence and Raman results confirms the assumption that there is no relaxation in the wells. The effects of uncertainties in the stress deformation potentials and phonon coefficients on strain determination have been discussed. The authors' results show that photoluminescence is an adequate tool to characterize InGaAs strained layers.
329.6Кб