Characterization of ZnMgSSe/ZnSe quantum wells grown by MOVPE

ZnMgSSe/ZnSe quantum wells grown by metalorganic vapour phase epitaxy (MOVPE) were investigated by photoluminescence (PL), photoluminescence excitation (PLE), reflection and X-ray diffraction spectroscopy. The binding energy of confined excitons in the wells was calculated with the fractional dimension model. In a 4 nm quantum well with 3.318 eV ZnMgSSe barriers, the exciton binding energy was 1.7 times the bulk value of ZnSe. From comparison of the calculated and measured transition energies in the ZnMgSSe/ZnSe quantum wells we could identify the e(1)hh(1) and e(1)lh(1) transitions. The e(1)hh(1) transition dominates in the PL spectrum whereas both e(1)hh(1) and e(1)lh(1) transitions appear in the PLE spectrum. The relative ratios of the conduction band discontinuities and the band-gap differences (Delta E-g) were between 23 and 17% for Delta E-g between 222 and 515 meV. (C) 1998 Elsevier Science B.V. All rights reserved.