Lattice-matched InxGa1-xAs/InxAl1-xAs quantum wells (x=0.18 and 0.19) grown on (411)A- and (100)-oriented InGaAs ternary substrates by molecular beamepitaxy

High-optical quality lattice-matched InxGa1-xAs/InxAl1-xAs quantum MTlls (Q Ws) with indium contents of x = 0.18-0.19 have been successfully grown on ( 4 1 1)A- and (1 0 0)-oriented InGnAs ternary substrates by molecular beam e pitaxy. Strong photoluminescence (PL) with a narrow linewidth was observed from both (4 1 1)A and (1 0 0) QWs at 12 K. The peak energy of PL from QWs had a good correlation with the calculated exciton emission energy based on the band parameter of the InGaAs well layers and InAlAs barrier layers. Th e result indicates that the (4 1 1)A and (1 0 0) InGaAs/InAlAs QWs on InGaA s ternary substrates have 0.2 eV larger energy gap difference between their well and barrier materials than GaAs/AlAs QWs on GaAs binary substrates or InGaAs/InAlAs QWs on InP binary substrates. In addition, the (4 1 1)A In0. 18Ga0.82As/In0.18Al0.82As QWs had a narron cr PL linewidth than (1 0 0) QWs indicating that smoother interfaces were realized in the (4 1 1)A QWs. (C) 2001 Elsevier Science B.V. All rights reserved.