The effects of both surface segregation of In atoms and strain on the confinement profile of InGaAs/GaAs multi quantum wells

The effects of indium segregation on exciton binding energy and oscillator strength in GaInAs/GaAs quantum wells

“…As seen from the figure, the exciton transition energies are found to be shifted to higher energies due to indium segregation, and increase with the increase of segregation coefficient R, which is in good agreement with the experimental results in Refs. [8,9,12,37,38]. The surface segregation of indium atoms leads to the change of the effective bandgap or the effective well width in the well.…”

“…For a fixed narrow well, the exciton oscillator strength decreases with the increase of segregation coefficient R, however for a fixed wide well, the exciton oscillator strength increases with the increase of segregation coefficient R. In real optical device, in order to utilize the quantum confinement effect, the width of quantum well is often less than 40 ML, therefore indium segregation degrades the optical properties of GaInAs/GaAs quantum wells, which is in good agreement with the experimental results in Refs. [8,37,38].…”

The influence of the growth temperature and interruption time on the crystal quality of InGaAs/GaAs QW structures grown by MBE and MOCVD methods

“…Realization of high-performance devices requires flat and abrupt QW interfaces and high crystal quality. The problem of optimization of growth conditions is still open, despite many experiments devoted to investigation of InGaAs QW quality dependence on alloy ordering and interface abruptness [5][6][7][8]. The difficulty comes from the fact that a number of different phenomena, both physical and technological, require tuning during the epitaxial process [9,10].…”