PHOTOLUMINESCENCE MEASUREMENTS OF TENSILE-STRAINED GAAS IN0.07AL0.93AS QUANTUM-WELLS/

GaAs/In0.07Al0.93As tensile-strained quantum wells were grown on [001] GaAs substrates using molecular-beam epitaxy. The incorporation of te nsile strain is made possible by preparing a 1-mu m-thick In0.07Al0.93 As relaxed buffer which is followed by the growth of quantum wells. Th e strain of the GaAs was measured using Raman spectroscopy and photolu minescence. The photoluminescence measurements from wells ranging in t hickness from 25 to 100 Angstrom reveal that the observed optical tran sition originates from the electron-light hole recombination for a 100 Angstrom well and from the electron-heavy hole recombination if the w ell thickness is less than 40 Angstrom. Therefore, a thick Al-rich Inx Al1-xAs relaxed buffer on the GaAs substrate can be used to engineer t he relative energy position of the light and heavy holes for GaAs-base d quantum wells. (C) 1996 American Institute of Physics.