Critical layer thickness in MOCVD grown InGaAsGaAs strained quantum wells

A series of In0.14Ga0.86AsGaAs quantum well structures have been grown by metal organic chemical vapor deposition (MOCVD). The measured dependence of photoluminescence (PL) energies on well width is compared with calculation. By the energy shift, line width and intensity change of PL spectroscopy, critical layer thickness has been identified. The critical layer thickness obtained for MOCVD grown material was found in agreement with theoretical value, but is smaller than molecular beam epitaxy grown ones.