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The effects of proton irradiation (1.5 MeV) on photoluminescence intensities and carrier dynamics were compared between III-V quantum dots and similar quantum well structures. A significant enhancement in radiation tolerance is seen with three-dimensional (3D) quantum confinement. Measurements were carried out in different quantum dot (QD) structures, varying in material (InGaAs/GaAs and InAlAs/AlGaAs), QD surface density (4×108 to 3×1010 cm-1), and substrate orientation [(100) and (311) B]. Similar trends were observed for all QD samples. A slight increase in PL emission after low to intermediate proton doses is also observed in InGaAs/GaAs  QD structures. The latter is explained in terms of more efficient carrier transfer from the wetting layer via radiation-induced defects.