  We analytically compute the power spectrum of primordial curvature
perturbations in Type III hilltop inflation models under the slow-roll
approximation. The model parameters are constrained using current Cosmic
Microwave Background (CMB) data. The curvature perturbations that exit the
horizon at small scales show sufficiently large amplitudes to produce
primordial black holes (PBHs). We then consider the quantum one-loop
corrections in these models from both the self-interaction of the inflaton and
its interaction with the waterfall field. We show the loop corrections in both
cases for 60 e-folds of inflation are negligible, ensuring the tree-level
results are reliable within the chosen parameter regime.
