The low-temperature grown AlGaAs/GaAs multiple quantum well structures were characterized by photoluminescence (PL) spectroscopy. The samples were grown at 270–400 °C and annealed at 500–900 °C. After anneal, photoluminescence quenching was observed for the samples grown at temperatures below 350 °C, and found to show a strong dependence on the growth and anneal temperatures. The luminescence intensity for the PL-quenched sample exhibits a power law dependence on the excitation level with an exponent close to 2, indicating a bimolecular recombination process in parallel with strong nonradiative recombination. The photoluminescence quenching upon anneal is attributed to the formation of arsenic clusters that serve as new nonradiative recombination channels. ©1998 American Institute of Physics.