Optical and structural characterizations of In/sub 0.53/Fa/sub 0.47/As/In/sub x/Ga/sub 1-x/As strained quantum wells on InP substrate

The authors combine photoluminescence (PL) experiments and reflection high-energy electron diffraction (RHEED) techniques to study the growth modes and the relaxation mechanism of strained InGaAs layers as a function of strain and growth temperature. It is well known that interface quality and relaxation can be assessed by the PL technique through the variations of the full width at half maximum (FWHM) and the intensity of the emission. PL measurements have been applied to investigate the electronic quality of single quantum wells (SQWs) consisting of strained InGaAs layers imbedded in lattice matched (LM) InGaAs. Optical results are correlated with structural ones obtained by in situ RHEED experiments on strained InGaAs layers. One can expect to grow relatively thick ( approximately=100 AA) highly strained metastable layers much thicker than the equilibrium critical thickness using low growth temperatures, which is very important for device applications. However, a compromise has to be found between lowering the temperature and keeping a good electronic quality of materials.<>