Self-assembled quantum dots (QDs) have attracted significant attention
because of their potential applications in novel semiconductor devices. In
this work, we investigated radiation effects induced by 1.0 MeV proton ion
beams on InAs self-assembled quantum dots. In particular, we emphasized the
effects of lattice environments of QDs on their luminescence emission after
ion beam irradiation. Photoluminescence (PL) spectroscopy was used to
characterize the optical properties of QDs subjected to proton irradiation
and post-irradiation annealing. Compared to the single-layer QDs grown in
GaAs films, the QDs embedded in an AlAs/GaAs superlattice exhibited much
higher PL degradation resistance to proton beam bombardment, e.g., at the
highest dose (1.0×1014 cm−2) used in this work, a
difference of ~ 20-fold in PL intensity was found between the QDs configured
in these two different lattice structures. After thermal annealing of
irradiated QD samples, ion beam enhanced blueshift of PL was observed to be
much more pronounced for the single-layer QDs. We discuss mechanisms that
may result in the differences in optical response to ion beams between QDs
with different lattice surroundings.